It's good to see a lot of other musical monks out there! I think it is not a coincidence; at my University there's a lot of Computer Science students that also play an instrument.

Regarding myself, I play bass. Not "bass guitar" :). Have been doing so for about nine years, mostly in church and jazz contexts. I also play guitar and sing, but not on stage :). And I'm getting into the composing & arranging thingie -- lots of fun.