According to the current discussion about the promotion of this site there come up the idea of a t-shirt with advertisement.
I want to collect some design ideas of a promotion t-shirt.
Edit: On a regular basis I try to give some preview links of good ideas (measured by the number of votes). Everybody is encouraged to do this on its own (especially if her/his favored idea doesn't get the most votes).
Edit2: Sorry for the long absence. I'm still going to look for a good T-shirt design. There are a lot of good ideas but I think we can get better ones :)