For those who don't know, Caffeine is a small program for Linux that lets a user prevent his or her computer from entering a power save state. If a user wishes, he or she can even configure caffeine to automatically inhibit power-saving when watching a flash movie, or running VLC, Totem etc. For more information, visit its website here.
As a user of both Caffeine and the new Humanity icon theme (the default icon theme in karmic), I made a very basic gray-scale version of the Caffeine icon. You can download it here.