Over the past few months I've been slowly getting rid of all my old, ripped t-shirts and slowly replacing them with new, cool t-shirts. A great, cheap place to shop for some unique designs is Woot Shirt. The basic concept is the site hosts a different shirt each day - if you want it, you have to buy it that day or else it goes away, never to return (unless it makes it by sheer popularity to the Reckoning List, where it will stay until voted off).
Buying a shirt the day it's offered is dirt cheap - $10 with free shipping. I bought a wicked D&D shirt designed by Wil Wheaton as well as a nice granola shirt of a tree in the shape of a guitar. Point being, there's lots of cool stuff to check out, including the below design, which I just got:
Looking for a cool shirt? Check 'em out - you could do a lot worse!