COMEDY: Tonight begins the 4th annual Sketchfest NYC, "dedicated to promoting the art of sketch comedy," which, they explain, "is different from improv and stand-up, [it] consists of short written scenes, rehearsed beforehand usually presented by a group of people" (as if you didn't know). All shows will be taking place at the UCB Theater; get the full schedule here -- The Harvard Sailing Team (pictured) kicks it all off at 7 p.m. 7 p.m.......