A Who’s Who of 30 Rock’s “Kidney Now!”

Do us a favor and fast forward through last night’s 30 Rock finale until you get to minute 17:30 — the supergroup’s performance of “Kidney Now!” — and try to ID as many of the 16 musicians involved as you can. (OK, it’s technically 17, but we refuse to count Clay Aiken, even if he is Kenneth’s cousin.) If you come up with more than six names, then you’ve bested us. The video and the full list after the jump.

Mary J. Blige
Elvis Costello
Sheryl Crow
Adam Horovitz
Adam Levine
Clay Aiken
Sara Bareilles
Mike Diamond
Steve Earle
Wyclef Jean
Norah Jones
Talib Kweli
Cyndi Lauper
Rhett Miller
Robert Randolph
Rachael Yamagata