Note: As of Nov 1 2010, SideTrack has been discontinued.
SideTrack is a replacement driver for Apple PowerBook and iBook trackpads. With SideTrack installed your standard trackpad becomes a powerful multi-button scrolling mouse. Leave your external mouse at home and take full control over your trackpad:
Vertical scrolling at left or right edge of pad
Map hardware button to left or right click
Map trackpad taps to no action, left click, left click drag (with or without drag lock), or right click
Map trackpad corner taps to mouse buttons 1-6 or simulated keystrokes