MyBattery 3.3.8 - Popular Pick Clean

MyBattery is a utility program designed specifically for
PowerBooks. It provides you with information about your PowerBook batteries and system. Its features include:

User-customizable display. You decide what
information you want to see.
Displays information about internal batteries,
including charging status, charge level and battery
voltage.
Estimate of useful battery time remaining. It uses a
historical estimation that "learns" from your PowerBook
usage patterns.
Displays power-related system information like hard
drive status, AppleTalk status, and modem status.
History window which displays recent battery charge
history, power consumption rate, and even temperatures
on some PowerBook models!
Support for multiple batteries, accommodating
different capacity batteries.
Menu bar displays, for easy viewing of battery status
and other system information.