GKrellM-PMU is a plugin for GKrellM to create a
battery monitor for Macintosh PowerBooks and
iBooks on Linux/PPC systems. Display includes such
things as dual battery support, time remaining,
and a load graph.
Information regarding Project Releases and Project Resources. Note that the information here is a quote from Freecode.com page, and the downloads themselves may not be hosted on OSDN.