Did you watch last week's 30 Rock? Do you remember when Liz was courted by the very attractive prostitute played by Eion Bailey? Turns out that wasn't a Joni Mitchell song playing over the fake club's sound system: it was Tina Fey herself, singing a fake Mitchell song called "Paint And Brushes." It's about tampons, I think:
I love Mitchell, but this is a pretty good impression of "All I Want." I now demand that Fey sing more on the show.