Caffeine for Windows - Prevent your computer from going to sleep
Caffeine for Linux - Inspired by the Mac OS X version, Caffeine for Linux is a status bar application able to...
noblackout - Disables screensaver and powersaving while running programms from a choosen directory.
Caffe1ne - Caffe1ne is a utility to keep your PC from locking, resting, or actuating screensaver after sit out of gear time dictated by different framework settings.
Insomniate - Insomniate is a highly lightweight application that keeps your PC from going into Sleep/Standby mode.
AntiSleep - AntiSleep is a powerful software that prevents the system from going into hibernate mode.