Short List

The three items on the previous Short List ("Musicians who had a cameo rôle as a shop keeper in a major Hollywood film") are:

Ray Charles in The Blues Brothers (Pavlov's Cat and MacHeath)
Ian Dury in Judge Dredd (Pavlov's Cat, again)
Bo Diddley in Trading Places (The Stigler)

Near misses (not cameo rôles):
Mos Def in Be Kind Rewind (DBC Reed)
Phil Collins (florist-cum-Great Train Robber) in Buster (The Stigler, again)

Doesn't count:
Henry Rollins as a doctor in Johnny Mnemonic (Richard Allan)

UPDATE: Make up your own minds whether this one counts:
Ricky Gervais (who was a musician before becoming a comedian/actor) in Stardust

UPDATE2: Tom Seddon (on the original post) asks: "Wouldn't Aretha Franklin count as well? She was in Blues Brothers as owner of the food place where the guitarist and saxophonist worked, and then again in Blues Brothers 2000 as owner of a car showroom." Pavlov's Cat/Macheath, any answers?
-------------------------------------
Next short list, and I can think of two (or three): "Television programmes, the title of which is based on/inspired by something/somebody in the book Nineteen Eighty-Four".