SleepWatcher 2.2 (running with Mac OS X 10.5 to OS X 10.10, source code included) is a command line tool (daemon) for OS X that monitors sleep, wakeup and idleness of a Mac. It can be used to execute a Unix command when the Mac or the display of the Mac goes to sleep mode or wakes up, after a given time without user interaction or when the user resumes activity after a break or when the power supply of a Mac notebook is attached or detached. It also can send the Mac to sleep mode or retrieve the time since last user activity. A little bit knowledge of the Unix command line is required to benefit from this software. For Mac OS X 10.3 and 10.4, use SleepWatcher 2.0.5 (and sources). For Mac OS X 10.1 and 10.2, download SleepWatcher 1.0.1. Some years ago, it was a Pick of the Week at Mac OS X Hints.