Start-ups that sell T-shirts are a dime a dozen, but a tool to let you search across all of the stores has been nonexistent. Enter PleaseDressMe, a simple search engine that lets you hunt for specialty T-shirts from several vendors at once using some simple filters.
Included are big-name online T-shirt stores like Threadless, BustedTees and TShirtHell. More will continue to be added, but for the time being the selection is far greater than any of those stores alone.
You can find the shirt you're looking for by keyword, tag, the color or price. You can also see shirts that the engine thinks are related. In my testing of this it tended to do a pretty good job, mostly basing the decision on color, although in one case it managed to pull together several shirts featuring boats or water from a T-shirt of Noah's Ark. That was impressive.
All links on the site lead to the online store where you can buy the shirt. Missing from the engine is some of the local color you'll find on those sites, like their user ratings, reviews, and photos of the shirt on actual people. Presumably the site plans to make its money off of affiliate linkage and sponsored results which are not yet a part of the picture.