http://www.pedalmafia.com/mafid/mafia_id.html
i'm sure everyone else has already seen this, but i just found it today, and think it's really cool.
if you haven't, it's a drag and drop bike designer. then you screen capture and crop, and voila, you've designed your bike.
i know i'm not dreaming big or anything, but this is what i want right now. just in 49cm