Marketed under the name "Softwear by Microsoft", they come in two lines: one consisting of "classic" designs (the old MS-DOS logo, circa Windows 3.0, the original Microsoft logo, and Bill Gates' mugshot from his 1970s driving conviction) and one co-designed with rapper Common, and involving references to the 1980s; there's one with some rap lyrics set in a monospaced font after a DOS prompt, and one featuring a pair of black-framed glasses and a pair of fluoro new-rave sunglasses.
It's not clear who will wear these. Pointy-haired boss types on casual Fridays? Visual Basic programmers who always wished they could wear cool geek T-shirts like the Linux guys but never actually understood any of the ThinkGeek ones? The guy in the office who regards himself to be with-it because he listens to Coldplay? Zune owners sick of being looked down on by those smug Mac users? Or are they expecting people to start wearing them ironically?
If only they'd produce a Windows ME one - I'd wipe my bum with it and mail it back to MS hq.