;DYou can't go wrong w/ a basic beanie like the one in Stitch and Bitch. I knit 4 of them out of plain merino wool then dyed them individually in Kool Aid packets for all of my friends last Christmas. It went over well.
My suggestion is to stick to a bulky yarn and you could be done inside of an hour. If you don't have the Stitch and Bitch book, try:http://www.knitty.com/ISSUEfall02/PATTdkhat.html
I made this hat a few weeks ago in about 3 hours (on a packed subway, so more like 2 hours