diff --git a/fastcore/_nbdev.py b/fastcore/_nbdev.py
index 1a1d8776..b4e6dfe3 100644
--- a/fastcore/_nbdev.py
+++ b/fastcore/_nbdev.py
@@ -53,6 +53,7 @@
          "store_attr": "01_basics.ipynb",
          "attrdict": "01_basics.ipynb",
          "properties": "01_basics.ipynb",
+         "camel2words": "01_basics.ipynb",
          "camel2snake": "01_basics.ipynb",
          "snake2camel": "01_basics.ipynb",
          "class2attr": "01_basics.ipynb",
@@ -164,6 +165,7 @@
          "sparkline": "03_xtras.ipynb",
          "autostart": "03_xtras.ipynb",
          "time_events": "03_xtras.ipynb",
+         "EventTimer": "03_xtras.ipynb",
          "stringfmt_names": "03_xtras.ipynb",
          "PartialFormatter": "03_xtras.ipynb",
          "partial_format": "03_xtras.ipynb",
diff --git a/fastcore/basics.py b/fastcore/basics.py
index 6830a5a6..20f72c9c 100644
--- a/fastcore/basics.py
+++ b/fastcore/basics.py
@@ -4,14 +4,14 @@
            'null', 'tonull', 'get_class', 'mk_class', 'wrap_class', 'ignore_exceptions', 'exec_local', 'risinstance',
            'Inf', 'in_', 'lt', 'gt', 'le', 'ge', 'eq', 'ne', 'add', 'sub', 'mul', 'truediv', 'is_', 'is_not', 'in_',
            'true', 'stop', 'gen', 'chunked', 'otherwise', 'custom_dir', 'AttrDict', 'type_hints', 'annotations',
-           'anno_ret', 'argnames', 'with_cast', 'store_attr', 'attrdict', 'properties', 'camel2snake', 'snake2camel',
-           'class2attr', 'getattrs', 'hasattrs', 'setattrs', 'try_attrs', 'GetAttrBase', 'GetAttr', 'delegate_attr',
-           'ShowPrint', 'Int', 'Str', 'Float', 'concat', 'detuplify', 'replicate', 'setify', 'merge', 'range_of',
-           'groupby', 'last_index', 'filter_dict', 'filter_keys', 'filter_values', 'cycle', 'zip_cycle', 'sorted_ex',
-           'not_', 'argwhere', 'filter_ex', 'range_of', 'renumerate', 'first', 'nested_attr', 'nested_idx', 'val2idx',
-           'uniqueify', 'num_methods', 'rnum_methods', 'inum_methods', 'fastuple', 'arg0', 'arg1', 'arg2', 'arg3',
-           'arg4', 'bind', 'map_ex', 'compose', 'maps', 'partialler', 'instantiate', 'using_attr', 'Self', 'Self',
-           'copy_func', 'patch_to', 'patch', 'patch_property', 'ImportEnum', 'StrEnum', 'str_enum', 'Stateful',
+           'anno_ret', 'argnames', 'with_cast', 'store_attr', 'attrdict', 'properties', 'camel2words', 'camel2snake',
+           'snake2camel', 'class2attr', 'getattrs', 'hasattrs', 'setattrs', 'try_attrs', 'GetAttrBase', 'GetAttr',
+           'delegate_attr', 'ShowPrint', 'Int', 'Str', 'Float', 'concat', 'detuplify', 'replicate', 'setify', 'merge',
+           'range_of', 'groupby', 'last_index', 'filter_dict', 'filter_keys', 'filter_values', 'cycle', 'zip_cycle',
+           'sorted_ex', 'not_', 'argwhere', 'filter_ex', 'range_of', 'renumerate', 'first', 'nested_attr', 'nested_idx',
+           'val2idx', 'uniqueify', 'num_methods', 'rnum_methods', 'inum_methods', 'fastuple', 'arg0', 'arg1', 'arg2',
+           'arg3', 'arg4', 'bind', 'map_ex', 'compose', 'maps', 'partialler', 'instantiate', 'using_attr', 'Self',
+           'Self', 'copy_func', 'patch_to', 'patch', 'patch_property', 'ImportEnum', 'StrEnum', 'str_enum', 'Stateful',
            'PrettyString', 'even_mults', 'num_cpus', 'add_props', 'typed']
 
 # Cell
@@ -311,9 +311,15 @@ def properties(cls, *ps):
     for p in ps: setattr(cls,p,property(getattr(cls,p)))
 
 # Cell
+_c2w_re = re.compile(r'((?<=[a-z])[A-Z]|(?<!\A)[A-Z](?=[a-z]))')
 _camel_re1 = re.compile('(.)([A-Z][a-z]+)')
 _camel_re2 = re.compile('([a-z0-9])([A-Z])')
 
+# Cell
+def camel2words(s, space=' '):
+    "Convert CamelCase to 'spaced words'"
+    return re.sub(_c2w_re, rf'{space}\1', s)
+
 # Cell
 def camel2snake(name):
     "Convert CamelCase to snake_case"
diff --git a/fastcore/xtras.py b/fastcore/xtras.py
index 05ec1fb4..f0a3bd47 100644
--- a/fastcore/xtras.py
+++ b/fastcore/xtras.py
@@ -3,8 +3,8 @@
 __all__ = ['dict2obj', 'obj2dict', 'repr_dict', 'is_listy', 'shufflish', 'mapped', 'IterLen', 'ReindexCollection',
            'maybe_open', 'image_size', 'bunzip', 'join_path_file', 'loads', 'untar_dir', 'repo_details', 'run',
            'open_file', 'save_pickle', 'load_pickle', 'truncstr', 'spark_chars', 'sparkline', 'autostart',
-           'time_events', 'stringfmt_names', 'PartialFormatter', 'partial_format', 'utc2local', 'local2utc', 'trace',
-           'round_multiple', 'modified_env', 'ContextManagers', 'str2bool', 'sort_by_run']
+           'time_events', 'EventTimer', 'stringfmt_names', 'PartialFormatter', 'partial_format', 'utc2local',
+           'local2utc', 'trace', 'round_multiple', 'modified_env', 'ContextManagers', 'str2bool', 'sort_by_run']
 
 # Cell
 from .imports import *
@@ -13,7 +13,7 @@
 from functools import wraps
 
 import mimetypes,pickle,random,json,subprocess,shlex,bz2,gzip,zipfile,tarfile
-import imghdr,struct,distutils.util,tempfile,time,string
+import imghdr,struct,distutils.util,tempfile,time,string,collections
 from contextlib import contextmanager,ExitStack
 from pdb import set_trace
 from datetime import datetime, timezone
@@ -222,9 +222,9 @@ def __repr__(self:Path):
     return f"Path({self.as_posix()!r})"
 
 # Cell
-def truncstr(s:str, maxlen:int, suf:str='…')->str:
+def truncstr(s:str, maxlen:int, suf:str='…', space='')->str:
     "Truncate `s` to length `maxlen`, adding suffix `suf` if truncated"
-    return s[:maxlen-len(suf)]+suf if len(s)>maxlen else s
+    return s[:maxlen-len(suf)]+suf if len(s)+len(space)>maxlen else s+space
 
 # Cell
 spark_chars = '▁▂▃▅▆▇'
@@ -236,10 +236,10 @@ def _sparkchar(x, mn, incr, empty_zero):
     return spark_chars[res]
 
 # Cell
-def sparkline(data, empty_zero=False):
+def sparkline(data, mn=None, mx=None, empty_zero=False):
     "Sparkline for `data`, with `None`s (and zero, if `empty_zero`) shown as empty column"
     valid = [o for o in data if o is not None]
-    mn,mx,n = min(valid),max(valid),len(spark_chars)
+    mn,mx,n = ifnone(mn,min(valid)),ifnone(mx,max(valid)),len(spark_chars)
     res = [_sparkchar(o,mn,(mx-mn)/n,empty_zero) for o in data]
     return ''.join(res)
 
@@ -260,6 +260,28 @@ def time_events():
     start,events = default_timer(),0
     while True: events += (yield events,events/(default_timer()-start)) or 0
 
+# Cell
+class EventTimer:
+    "An event timer with history of `store` items of time `span`"
+    def __init__(self, store=5, span=60):
+        self.hist,self.span,self.last = collections.deque(maxlen=store),span,default_timer()
+        self._reset()
+
+    def _reset(self): self.start,self.events = self.last,0
+
+    def add(self, n=1):
+        "Record `n` events"
+        if self.duration>self.span:
+            self.hist.append(self.freq)
+            self._reset()
+        self.events +=n
+        self.last = default_timer()
+
+    @property
+    def duration(self): return default_timer()-self.start
+    @property
+    def freq(self): return self.events/self.duration
+
 # Cell
 _fmt = string.Formatter()
 
diff --git a/nbs/01_basics.ipynb b/nbs/01_basics.ipynb
index 4622f22d..a4da60b6 100644
--- a/nbs/01_basics.ipynb
+++ b/nbs/01_basics.ipynb
@@ -1925,10 +1925,32 @@
    "outputs": [],
    "source": [
     "#export\n",
+    "_c2w_re = re.compile(r'((?<=[a-z])[A-Z]|(?<!\\A)[A-Z](?=[a-z]))')\n",
     "_camel_re1 = re.compile('(.)([A-Z][a-z]+)')\n",
     "_camel_re2 = re.compile('([a-z0-9])([A-Z])')"
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "#export\n",
+    "def camel2words(s, space=' '):\n",
+    "    \"Convert CamelCase to 'spaced words'\"\n",
+    "    return re.sub(_c2w_re, rf'{space}\\1', s)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "test_eq(camel2words('ClassAreCamel'), 'Class Are Camel')"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,
diff --git a/nbs/03_xtras.ipynb b/nbs/03_xtras.ipynb
index 35621ca4..891078e6 100644
--- a/nbs/03_xtras.ipynb
+++ b/nbs/03_xtras.ipynb
@@ -22,7 +22,7 @@
     "from functools import wraps\n",
     "\n",
     "import mimetypes,pickle,random,json,subprocess,shlex,bz2,gzip,zipfile,tarfile\n",
-    "import imghdr,struct,distutils.util,tempfile,time,string\n",
+    "import imghdr,struct,distutils.util,tempfile,time,string,collections\n",
     "from contextlib import contextmanager,ExitStack\n",
     "from pdb import set_trace\n",
     "from datetime import datetime, timezone\n",
@@ -618,7 +618,7 @@
     {
      "data": {
       "text/plain": [
-       "['d', 'c', 'h', 'a', 'b', 'g', 'e', 'f']"
+       "['a', 'e', 'h', 'b', 'g', 'd', 'c', 'f']"
       ]
      },
      "execution_count": null,
@@ -1326,9 +1326,9 @@
    "outputs": [],
    "source": [
     "#export\n",
-    "def truncstr(s:str, maxlen:int, suf:str='…')->str:\n",
+    "def truncstr(s:str, maxlen:int, suf:str='…', space='')->str:\n",
     "    \"Truncate `s` to length `maxlen`, adding suffix `suf` if truncated\"\n",
-    "    return s[:maxlen-len(suf)]+suf if len(s)>maxlen else s"
+    "    return s[:maxlen-len(suf)]+suf if len(s)+len(space)>maxlen else s+space"
    ]
   },
   {
@@ -1338,9 +1338,11 @@
    "outputs": [],
    "source": [
     "w = 'abacadabra'\n",
-    "test_eq(truncstr(w, 15), w)\n",
+    "test_eq(truncstr(w, 10), w)\n",
     "test_eq(truncstr(w, 5), 'abac…')\n",
     "test_eq(truncstr(w, 5, suf=''), 'abaca')\n",
+    "test_eq(truncstr(w, 11, space='_'), w+\"_\")\n",
+    "test_eq(truncstr(w, 10, space='_'), w[:-1]+'…')\n",
     "test_eq(truncstr(w, 5, suf='!!'), 'aba!!')"
    ]
   },
@@ -1374,10 +1376,10 @@
    "outputs": [],
    "source": [
     "#export\n",
-    "def sparkline(data, empty_zero=False):\n",
+    "def sparkline(data, mn=None, mx=None, empty_zero=False):\n",
     "    \"Sparkline for `data`, with `None`s (and zero, if `empty_zero`) shown as empty column\"\n",
     "    valid = [o for o in data if o is not None]\n",
-    "    mn,mx,n = min(valid),max(valid),len(spark_chars)\n",
+    "    mn,mx,n = ifnone(mn,min(valid)),ifnone(mx,max(valid)),len(spark_chars)\n",
     "    res = [_sparkchar(o,mn,(mx-mn)/n,empty_zero) for o in data]\n",
     "    return ''.join(res)"
    ]
@@ -1440,6 +1442,16 @@
     "This is convenient for tracking the frequency of events. Call `send(n)` any time you want to add `n` events to the counter. Pass the object to `next()` to get a tuple of the number of events and the frequency/second."
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Random wait function for testing `time_events`\n",
+    "def _randwait(): yield from (sleep(random.random()/200) for _ in range(100))"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,
@@ -1449,14 +1461,11 @@
      "name": "stdout",
      "output_type": "stream",
      "text": [
-      "# Events: 10, Freq/sec: 80.30\n"
+      "# Events: 100, Freq/sec: 396.51\n"
      ]
     }
    ],
    "source": [
-    "# Random wait function for testing `time_events`\n",
-    "def _randwait(): yield from (sleep(random.random()/30) for _ in range(10))\n",
-    "\n",
     "c = time_events()                # Start timer\n",
     "for o in _randwait(): c.send(1)  # Send an event\n",
     "events,freq = next(c)            # Return counter values\n",
@@ -1464,6 +1473,89 @@
     "print(f'# Events: {events}, Freq/sec: {freq:.02f}')"
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "#export\n",
+    "class EventTimer:\n",
+    "    \"An event timer with history of `store` items of time `span`\"\n",
+    "    def __init__(self, store=5, span=60):\n",
+    "        self.hist,self.span,self.last = collections.deque(maxlen=store),span,default_timer()\n",
+    "        self._reset()\n",
+    "\n",
+    "    def _reset(self): self.start,self.events = self.last,0\n",
+    "\n",
+    "    def add(self, n=1):\n",
+    "        \"Record `n` events\"\n",
+    "        if self.duration>self.span:\n",
+    "            self.hist.append(self.freq)\n",
+    "            self._reset()\n",
+    "        self.events +=n\n",
+    "        self.last = default_timer()\n",
+    "    \n",
+    "    @property\n",
+    "    def duration(self): return default_timer()-self.start\n",
+    "    @property\n",
+    "    def freq(self): return self.events/self.duration"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/markdown": [
+       "<h4 id=\"EventTimer\" class=\"doc_header\"><code>class</code> <code>EventTimer</code><a href=\"\" class=\"source_link\" style=\"float:right\">[source]</a></h4>\n",
+       "\n",
+       "> <code>EventTimer</code>(**`store`**=*`5`*, **`span`**=*`60`*)\n",
+       "\n",
+       "An event timer with history of `store` items of time `span`"
+      ],
+      "text/plain": [
+       "<IPython.core.display.Markdown object>"
+      ]
+     },
+     "metadata": {},
+     "output_type": "display_data"
+    }
+   ],
+   "source": [
+    "show_doc(EventTimer, title_level=4)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Add events with `add`, and get number of `events` and their frequency (`freq`)."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Num Events: 5, Freq/sec: 646.7\n",
+      "Most recent:  ▁▇▃▇▆ 259.5 450.4 362.1 441.0 427.9\n"
+     ]
+    }
+   ],
+   "source": [
+    "c = EventTimer(store=5, span=0.03)\n",
+    "for o in _randwait(): c.add(1)\n",
+    "print(f'Num Events: {c.events}, Freq/sec: {c.freq:.01f}')\n",
+    "print('Most recent: ', sparkline(c.hist), *L(c.hist).map('{:.01f}'))"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,