Two t-shirts for those afflicted with seasonal affective disorder: s.a.d. t-shirt 01 and s.a.d. t-shirt 02. Both shirts feature inks that reveal hidden elements when worn in the sun or warm weather. (Psst, Hypercolor shirts are back and, yes, I'm a bit OMGWMCC about it. What, it's not possible to buy your childhood back?) (Psst, oh my God, where's my credit card?)
Update: For whatever reason, the site featuring those tshirts has been taken down. today and tomorrow grabbed some of the pics though.