I know, I know: you hate minor posts. I get it, but I just noticed that one of fave Linux artists, 0rAX0, has uploaded an Elementary icon for Caffeine, the cool power-inhibiter application.
You can download the icons from gnome-look.org. After which, install them by extracting the archive and placing the resulting icons in /usr/share/caffeine/images. Then, restart the application and et voila – elementary-style icons.
Neat, no?