Oh, yeah. The Bare Midriff Section is the three girls who sing backup.

At every concert, they sing "The Steely Dan Show" and one other song as the only vocals. When I saw them, the other song was Parker's Band; I think there are a couple others they do too.

They're also really pretty and have really, really nice outfits. (the three girls all match, but differ in neat artistic ways. there're pictures in the concert archives...)