If you're looking for some T-shirt on the halfshell, Threadless has you covered, as they've released 15 shirts featuring the Teenage Mutant Ninja Turtles -- as well as Shredder, Krang, Splinter and other characters from the comics and TV show. The Turtles join a growing number of shirts based on comics and/or cartoons at Threadless, which already include Marvel superheroes and various other Disney properties.

The above shirt, "Face Your Doom!!" by Matthew Skiff, is probably my favorite, and I've included a few more I liked below.