This is actually the first shirt I've gotten for this particular project. It was secret for so long! I've actually gotten a few shirts out of Palm though; there was a polo shirt for beta testing the Palm Backup software, a grey t-shirt with a wire frame model of the Treo 680, the "Spring Launch '05" t-shirt that came out with the LifeDrive and features icons of a flower, a rocket ship, and 05 all in a row. My favorite shirt was from last summer when Palm had it's 10-year anniversary of the PalmPilot; it's another black t-shirt, but it has a reproduction of the napkin sketch that Jeff Hawkins made of the original Pilot 1000, the product that started the whole mess.
I got a couple of shirts out of PalmSource, but most were generic logo tees. My favorite was a bright purple shirt that we gave out for a developer sync-up for a project that was codenamed Dialtone. The shirt doesn't mention the codename, but below the PalmSource logo there's the caption "350Hz + 440Hz" which references the two frequencies that go together to make a dial tone signal in the US phone system.
When I was at Metrowerks, I accumulated a lot of shirts. I still have a couple of the "CodeWarrior for Be" and "CodeWarrior for OS-9" shirts that were new when I started. I've got one of the alien "They use CodeWarrior" shirts that's well-worn, and there's a lot of now-useless CodeWarrior-logo golf-shirts hanging in my closet at home.
I don't remember getting any interesting shirts at Motorola; I've got a Veriprise t-shirt around, but nothing that mentions any of our products, although there's a VChat sticker on my badge from the 2000 PalmSource show. I hear there's a big corporate party the week that I head to California, so maybe I'll come back with yet-another-shirt to add to my growing collection.