Zazzle had a few different options for me--though I'm still waiting for a tee with Nightcrawler's iconic "BAMF!!" cloud (there's a lot of BAMF shirts, but they're riffing off the "Bad A$$ Mo-fo" idea.) It's available in Britain, grumble, but they're not shipping to the US yet.
So they had a couple of cute ones :) One had a picture of a "Safety Man" style guy teleporting across the shirt, with the caption "Rules of Teleportation," so I got two of those in different colors. But the BEST one was a little oval that said "Teleport Magic" on it--perfect :)
One that I thought about but didn't get was a cute one for Harry Potter fans that said "My Heart is Splinched Without You," which was nice, but the reference is a little specific, there's a bit of a "TLDR" thang (particularly on a t-shirt, one that's likely to be obscured by a vest), and, as Whines pointed out, blink dogs don't splinch, that's for other, lesser teleporters.
Hmm...would I wear the "Team Displacer Beast" shirt, or not? That's difficult.