Friend of HeroMachine John and I rocked these shirts from Boomtube Gear ("Apparel and Gear for the Discriminating Geek!") at Dragon*Con this year. I think they're brilliant, the perfect combination of geekery and subtlety one expects from the discerning geek. Those in the know will know, while those who are not will not. You can fly under the radar AND look awesome to our people! Check 'em out:
The shirts are super (get it?!) high quality and the designs are excellent. They'd make a great gift for the knowledgeable nerd in your group of friends, even if that nerd is you. I give it the highest possible HeroMachine ranking of love, so please check them out! He's got more designs coming soon, as well.