San Francisco'sB and Not Bhauled themselves all over the Mission playing Led Zeppelin'sImmigrant Songout of a rented van. They documented it and have managed to generate a pretty decent amount of buzz.
B and Not B's record is due out soon but in the meantime, check out theirsite, sign up for their mailing list and get a sneek peek with a free Mp3.
Also, on a similar note, they've also helped me deal with the PTSD that came after seeing this same song used in the trailer for the 3rd Shrek movie. Thanks guys!