We're going to play 'Don't Take Me Alive' by Steely Dan. Right at the end, it vamps twice, and then ends. I thought this was a perfect little progression to work out some jazzy licks.
We're playing it in, what I think is the original key of Eb/c. The vamp is:
Fm7 - Gm7 - Abmaj7 - Bb
so, a nice, kind of modal flavor for Eb. Whaddaya think?