Flash Block is a menu bar app for easily toggling the flash browser plugin on and off.

When you need to maximise your Mac's battery life, enable flash block to prevent flash ad banners on webpages from needlessly consuming your CPU and battery.

There are two options:
1. Auto Kill Flash (always detects and disables Flash)
2. Kill Active Flash (only disables currently loaded Flash plugins - they will reappear if you refresh the page)

Supports FireFox, Chrome and of course, Safari.