I must say, I'm a total geek, and making geeky things is generally my main reason for crafting. When you love a tv show, or film, or even a book, it's natural to want to make something to express your love. Here's my attempt at the geeky craft classic, Jayne's hat from Firefly. I made it for a friend years ago, and crocheted it because I can't knit.
So I love this site: http://geekcrafts.com/do-or-do-not-there-is-no-try/
Geek Crafts had the good taste to post about my Star Wars amigurumi patterns, but they've got posts about so many adorable geeky crafts I could spend ages on there!