When researching this week's Ask TUAW I ran across a nifty little utility for reclaiming the function keys on a Mac portable or recent Apple external keyboard. Basically, FunctionFlip allows you to set the individual function keys to be regular F-keys instead of those special control keys (brightness, volume, iTunes, etc.).
While the Keyboard Preference Pane will let you flip all of the keys one way or the other, FunctionFlip lets you individually choose which ones you want. That way you can preserve whichever of the control functions you like, but regain access to certain of the F-keys without having to hold down the fn key. It can be a handy way to have your cake and eat it too.
FunctionFlip is a free download (donations requested) from Kevin Gessner.