Kid Congo Powers.  Yoga's post re Cave/Seeds prompted me to think of the Kid.  An original member of the Gun Club, part of the best lineup of the Cramps, and a former Bad Seed....so a formative part of 3 of the most important/best underground bands of a generation.  And he's now found his voice (i.e. writes songs....not trying to beat a dead horse!)

Dave Cloud - Now known (though usually unknowingly) by millions due to "Trash Humpers" and the Budweisers telly ads....the guy is the outsider's outsider.  Musically, I love him.....simple, primal, catchy trash.  Unintentional (I think) performance art.  THEE most charming man I've ever met.  And wonderfully eccentric.

Thee Spivs - Have mentioned them here before.  To me (a Bostonian), the Clash were the voice of London in the 70s.  To me, Thee Spivs are the voice of today's London.