Mac OS X only: Free application FunctionFlip adds a new preference pane to your Mac's System Preferences that lets you choose which function keys you want to operate purely as standard function keys versus special keys on a per-case basis. Say for example that you like the volume keys instead of the corresponding function keys, but you don't want to dedicate function keys to your controlling iTunes (or some version of this scenario). Normally you can only choose all function keys or all special keys by default. With FunctionFlip, you say which keys operate as special keys and which operate as the default function key (e.g., F1, F2, etc.). FunctionFlip is a simple but smart piece of freeware, Mac OS X only.