Tweak F-Key functionality on a per-App basis?

I like being able to use the F-Keys on my keyboard to perform the assigned special features printed on each key (brightness +/-; Spaces; Expose; iTunes Playback Controls; etc) without having to press the 'Fn' modifier key to do so.

However, when I work in Photoshop, I've always used the F-keys to run Actions and to execute menu items, and having to tack on the 'Fn' key to do so is a series buzz kill (especially when you consider I already use multiple modifier keys along with the F-keys in Photoshop - for example Shift+Cmd+F2 might do something like add a Hue/Saturation Layer... when you complicate an already complicated shortcut by making it Fn+Shift+Cmd+F2, the shortcut basically becomes to complex to use in real life...

Anyone know of a third party System Preference Pane 'haxie' (or something along those lines) that would allow me to configure, on a per-application basis, the 'Fn' modifier key and whether or not it will be required for single button usage of Apple's various special features, or for standard F-Key functionality)?

Any suggestions would be greatly appreciated... Thanks!