they do make fully configurable graphical keyboards, where each key is a full color 64x64 (?) pixel display. they are insanely expensive though... well into the hundreds or even thousands of dollars. I would think a keyboard extension with 15 or 20 keys like that would be very helpful for developers. keys for building, debugging commands, etc. you could even develop a plugin for your favorite IDE to access those keys, and have various "scenes" depending on what task you're working on, whether it be editing code, debugging or whatever.
edit: the optimus maximus keyboard