Sounded nice but doesn't work on El Capitan 10.11.1 when I tried adding 'America/Los_Angeles' as one of the clocks. Hope the bug report helps. Added as https://github.com/Abhishaker17/Clocker/issues/1

console logs show this:

```
14/11/2015 20:55:38.088 lsd[255]: LaunchServices: Could not store lsd-identifiers file at /private/var/db/lsd/com.apple.lsdschemes.plist
14/11/2015 20:55:40.034 Clocker[47726]: * -[NSCalendar component:fromDate:]: date cannot be nil
14/11/2015 20:55:40.040 Clocker[47726]: (
0 CoreFoundation 0x00007fff987afe32 __exceptionPreprocess + 178
1 libobjc.A.dylib 0x00007fff95c1bdd4 objc_exception_throw + 48
2 CoreFoundation 0x00007fff98786b5c -[NSCalendar component:fromDate:] + 316
3 Clocker 0x00000001062b678e Clocker + 26510
4 Clocker 0x00000001062b6924 Clocker + 26916
5 Clocker 0x00000001062b61e3 Clocker + 25059
6 AppKit 0x00007fff9a76cd54 -[NSTableView(NSTableViewViewBased) makeViewForTableColumn:row:] + 76
7 AppKit 0x00007fff9a76c76d -[NSTableRowData _addViewToRowView:atColumn:row:] + 283
8 AppKit 0x00007fff9a76c4c6 -[NSTableRowData _addViewsToRowView:atRow:] + 184
9 AppKit 0x00007fff9a76acdf -[NSTableRowData _initializeRowView:atRow:] + 390
10 AppKit 0x00007fff9a76943f -[NSTableRowData _addRowViewForVisibleRow:withPriorView:] + 416
11 AppKit 0x00007fff9a7691d3 -[NSTableRowData _addRowViewForVisibleRow:withPriorRowIndex:inDictionary:withRowAnimation:] + 299
12 AppKit 0x00007fff9a767f99 -[NSTableRowData _unsafeUpdateVisibleRowEntries] + 1697
13 AppKit 0x00007fff9a76785a -[NSTableRowData updateVisibleRowViews] + 233
14 AppKit 0x00007fff9a7671d3 -[NSTableView layout] + 178
15 AppKit 0x00007fff9a7060df -[NSView _doLayout] + 53
16 AppKit 0x00007fff9a705d97 -[NSView _layoutSubtreeWithOldSize:] + 324
17 AppKit 0x00007fff9a705ff3 -[NSView _layoutSubtreeWithOldSize:] + 928
18 AppKit 0x00007fff9a67819b -[NSView setFrameSize:] + 1727
19 AppKit 0x00007fff9a69f620 -[NSClipView setFrameSize:] + 390
20 AppKit 0x00007fff9a6905b5 -[NSView setFrame:] + 476
21 AppKit 0x00007fff9a63829b -[NSScrollView _setContentViewFrame:] + 633
22 AppKit 0x00007fff9a635fd3 -[NSScrollView tile] + 2563
23 AppKit 0x00007fff9a635547 -[NSScrollView _tileWithoutRecursing] + 51
24 AppKit 0x00007fff9a6a21fb -[NSScrollView _update] + 27
25 AppKit 0x00007fff9a69ef42 NSViewLevelLayout + 165
26 AppKit 0x00007fff9a69ee87 -[NSView layout] + 14
27 AppKit 0x00007fff9a74a660 -[NSScrollView layout] + 56
28 AppKit 0x00007fff9a7060df -[NSView _doLayout] + 53
29 AppKit 0x00007fff9a705d97 -[NSView _layoutSubtreeWithOldSize:] + 324
30 AppKit 0x00007fff9a67819b -[NSView setFrameSize:] + 1727
31 AppKit 0x00007fff9a71f416 -[NSScrollView setFrameSize:] + 1147
32 AppKit 0x00007fff9a6905b5 -[NSView setFrame:] + 476
33 AppKit 0x00007fff9a69cbd5 -[NSView resizeWithOldSuperviewSize:] + 409
34 AppKit 0x00007fff9a69c569 -[NSView resizeSubviewsWithOldSize:] + 318
35 AppKit 0x00007fff9a69ef42 NSViewLevelLayout + 165
36 AppKit 0x00007fff9a69ee87 -[NSView layout] + 14
37 AppKit 0x00007fff9a7060df -[NSView _doLayout] + 53
38 AppKit 0x00007fff9a705d97 -[NSView _layoutSubtreeWithOldSize:] + 324
39 AppKit 0x00007fff9a67819b -[NSView setFrameSize:] + 1727
40 AppKit 0x00007fff9a6905b5 -[NSView setFrame:] + 476
41 AppKit 0x00007fff9a69cbd5 -[NSView resizeWithOldSuperviewSize:] + 409
42 AppKit 0x00007fff9a69c569 -[NSView resizeSubviewsWithOldSize:] + 318
43 AppKit 0x00007fff9a6781b7 -[NSView setFrameSize:] + 1755
44 AppKit 0x00007fff9a80934b -[NSNextStepFrame setFrameSize:] + 201
45 AppKit 0x00007fff9a6905b5 -[NSView setFrame:] + 476
46 AppKit 0x00007fff9a69cedd -[NSView resizeWithOldSuperviewSize:] + 1185
47 AppKit 0x00007fff9a7052a0 -[NSView layoutSubtreeIfNeeded] + 902
48 AppKit 0x00007fff9a724be5 -[NSWindow(NSConstraintBasedLayout) _layoutViewTree] + 82
49 AppKit 0x00007fff9a70b5e2 -[NSWindow _setFrame:updateBorderViewSize:] + 1059
50 AppKit 0x00007fff9a72403d -[NSWindow _oldPlaceWindow:] + 1075
51 AppKit 0x00007fff9a723426 -[NSWindow _setFrameCommon:display:stashSize:] + 2719
52 AppKit 0x00007fff9a722979 -[NSWindow _setFrame:display:allowImplicitAnimation:stashSize:] + 222
53 AppKit 0x00007fff9a722894 -[NSWindow setFrame:display:] + 67
54 Clocker 0x00000001062b5c1f Clocker + 23583
55 Foundation 0x00007fff8a715835 -[NSObject(NSKeyValueObservingPrivate) _changeValueForKey:key:key:usingBlock:] + 1049
56 Foundation 0x00007fff8a780ef7 _NSSetCharValueAndNotify + 268
57 Clocker 0x00000001062b77df Clocker + 30687
58 libsystem_trace.dylib 0x00007fff8b934082 _os_activity_initiate + 75
59 AppKit 0x00007fff9a8bb811 -[NSApplication sendAction:to:from:] + 460
60 Clocker 0x00000001062b4f95 Clocker + 20373
61 AppKit 0x00007fff9ae1842d -[NSWindow _handleMouseDownEvent:isDelayedEvent:] + 6322
62 AppKit 0x00007fff9ae19411 -[NSWindow _reallySendEvent:isDelayedEvent:] + 212
63 AppKit 0x00007fff9a85eb8d -[NSWindow sendEvent:] + 517
64 AppKit 0x00007fff9ad27155 -[NSStatusBarWindow sendEvent:] + 281
65 AppKit 0x00007fff9a7deb27 -[NSApplication sendEvent:] + 2540
66 AppKit 0x00007fff9a645d9a -[NSApplication run] + 796
67 AppKit 0x00007fff9a60efbe NSApplicationMain + 1176
68 libdyld.dylib 0x00007fff8bd805ad start + 1
)
14/11/2015 20:55:40.059 com.apple.xpc.launchd[1]: (com.abhishek.Clocker.149152[47726]) Service exited due to signal: Illegal instruction: 4
14/11/2015 20:55:40.113 com.apple.xpc.launchd[1]: (com.apple.ReportCrash[47730]) Endpoint has been activated through legacy launch(3) APIs. Please switch to XPC or bootstrap_check_in(): com.apple.ReportCrash
14/11/2015 20:55:40.537 ReportCrash[47730]: Saved crash report for Clocker[47726] version 1.0 (9) to /Users/username/Library/Logs/DiagnosticReports/Clocker_2015-11-14-205540_UserNames-MacBook-Pro.crash
```