TigerToggle:
TigerToggle is an Applescript application for turning Dashboard and/or Spotlight
on and off. Using this app will absolutely void your warranty!
ADVANCED USERS ONLY! USE AT YOUR OWN RISK! Et cetera. Useful for people who have
old, slow machines that don't handle OS X version 10.4's extra features well,
or for turning off those memory-hogging features before performing a 3D render
or other resource-intensive operation. Requires OS X version 10.4 or later and
the BSD subsystem.