I think that we should create some sort of sweet standard t-shirt design so we can all make our own t-shirts and run around wearing them. I was thinking putting a big TI|BD slanted upwards on the front with a big color splash behind it and on the back put the words
"TI-Basic Developer" and
"Your World, Nerdier"
also the text would be white, the backdrop black, and the color splash would be silver-ish.
Another option would be to have hats that just have the TI|BD flat on the front and the "Your World, Nerdier" on the back.