I wear exclusively Gap favorite stretch Ts (I have nine, in five colors) with two exceptions. One is a Barry O shirt that the lovely people at MoveOn sent me and I wore when canvassing to give people a far-off visual that I wasn't coming to their house to sell them giftwrap or the way to heaven (and still wear because who would have thought that shirt would be so excellent!), and one is a t-shirt from Threadless. It's really (unexpectedly, to me) well made and fits great and gets me a heck of a lot of compliments. I think there's a lot of blah or huh or urgh stuff on there but every once in a while there's a gem that aspires to the ranks of the favorite and the president. Go Threadless.
$18 at Threadless