A prediction: The theater of the (near) future will be excellently written but barely rehearsed one-night performances. Saturday Night Live, basically, but smaller, better, and actually live, not “TV-live.” Sandbox Radio Live is like that: sketches by kick-ass local theater people, including a gloriously moody serial about an exiled angel-detective written by Paul Mullin and starring Charles Leggett. For anyone who’s sat through an episode of SNL and felt let down—and who hasn’t?—check out SRL. (West of Lenin, 203 N 36th St, www.brownpapertickets.com, 8:00 pm, technically free because of idiotic union regulations but bring some bucks to share)