Shuriken
Shuriken is an XML-based tool for Linux system administrators to set up spans of time when the system should be up. Using the RTC daily alarm (requires BIOS, hardware, Linux support), the system will automatically power on (if it is off) for these intervals. The man pages provide all the documentation for the tools provided.
Releases: Shuriken v1.0 Released
Last Modified: 2003-07-22T00:36Z
Not following the trend of most Open Source projects, the first public release of Shuriken is v1.0. There may be a few bugs in this release (although everything works on my system), but all of the features are present and documented (see the man pages, especially shuriken(7) for documentation).
Future plans include bug fixes and maybe a GTK+ front-end to uptab(8) to make maintenance easier (although I assume that most interaction with uptab(8) is scripted).
If Shuriken works correctly on your hardware, feel free to post your motherboard, BIOS, and Linux specs in the forums and I'll make a list of supported platforms.