Fortran IV writes: Randall Munroe's xkcd webcomic has done some odd things before, but #1190, "Time," is something special. It's a time-lapse movie of two people building a sandcastle that's been updating just once an hour (twice an hour in the beginning) for well over a month (since March 25th), and after over a thousand frames shows no sign of ending; in a few days the number of frames will surpass the total number of xkcd comics. It's been mentioned in The Economist. Some of its readers have called it the One True Comic; others have called it a MMONS (Massively Multiplayer Online Nerd Sniping). It's sparked its own wiki, its own jargon (Timewaiters, newpix, Blitzgirling), and a thread on the xkcd user forum that runs to over 20,000 posts from 1100 distinct posters. Is "Time" a fascinating work of art, a deep sociological experiment—or the longest-running shaggy-dog joke in history? Randall Munroe's not saying.