One of my highlights from the Game Developers' Conference for me was the "Oh No Banjo" exhibit, showing off student work from the Rochester Institute of Technology's "Alternative Controllers Seminar." The students gutted a guitar game-controller and built a very credible banjo using its buttons and electronics, then wrote custom software and musical arrangements for it (apparently the Scruggs people rightsholders wouldn't let them use "Duelling Banjos," even for a noncommercial, student project). I played it for a while and found it very fun — I totally rocked the banjo for MC Chris's "Fett's Vette."
Final Reports and Pictures from the Alternative Controllers Seminar