Not sure if this is well known or not, but it's new to me. Friend just linked it to me and I thought it was pretty snazzy.

http://www.thinkgeek.com/computing/input/9836/

Basically, each key has an OLED screen on it. You can customize what shows up there, whether its an image (animated also) or even a quicktime movie it says in there. Would be pretty snazzy for what we do to have that (kind of like how you see those XKey Pros with the wow icons, except without all the printout and cutout work!).

The only downside of course is that its a new technology and currently costs about 1600 bucks... Will have to wait and see when the price drops.