Raise a little green for a green cause at the fourth annual Rock Lottery, a benefit for the Greening of Detroit. The concept is simple — 60 local musicians are randomly organized into 15 one-off groups that are given a week to prepare one original and one cover ditty, which they'll perform for the eco-friendly masses. The member swapping shenanigans (oh my!) take place at 8 p.m. at the Magic Stick, 4120 Woodward Ave., Detroit; 313-833-9700; $10; all ages.