I decided to go as Mario for Halloween at work today. In addition to the Mario costume, I also got a Luigi costume. This costume totally brings out the geek in me, but my alternatives weren't really that good. I would get a kick out of dressing up like Peter Gibbons, but I'd just blend in. It would be hard to go as any character from xkcd.com
, but that would also be sweet; I guess Mario will have to do.