Paper aviation
Spotted a memepool entry about paper airplanes, citing this complex design as the best (also: lots more designs). But I can’t imagine that any of these flies as well as Joe Palmer’s planes, especially when you consider that no tearing or cutting is required. (The PL-1 is extraordinarily easy to fold, too—only a couple steps away from the old dart that everyone knows how to fold, but which flies straight into the pavement.)
And while we’re talking about paper planes, be sure to grab a copy of Glider PRO, now that John Calhoun’s made it freely available.