XKCD, a webstore of romance, sarcasm, math and language, is the online shop of their webcomic. Check out XKCD to get a feel for their style of warped science. The original cartoons have a double punchline with rollover text sometimes elucidating the underlying concept, though more often than not merely serving to deepen the confusion. A handy and active forum serves to explain away the mysteries to those who didn't get the joke.
The XKCD webstore has the usual merchandise of signed prints, posters, T-shirts and apparel. The Tech Support T-shirt is very popular. The Linux Cheat Shirt - printed upside-down so that you can read it whilst wearing it - and the "Stand Back, I'm Going To Try Science" will make you stand out as a sociopath. But my favourite is the Useless T-shirt - even the identity matrix is useless in the face of love. Sadly, the material world of T-shirts makes it difficult to have hidden text but the obvious solution is to print it on the back (so why haven't they done so?)
Enjoy the comic and remember... "SCIENCE. It Works, Bitches." (lucky there's a comma there)
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