Now here is a keyboard that you might just want to check out if you have lots of extra cash to spend, the Optimus Popularis from Art Lebedev. Using the The Popularis keyboard users can customize tiny individual LCD displays running at 64 x 64 pixels resolution, the keys themselves can show different characters (switch to Hebrew or Greek letters with a click), show icons or graphics for your shortcuts or run macros.
For more info visit:
http://www.artlebedev.com/everything/optimus/popularis/