I came across a page for The Rock The Bells 2011 concert on Saturday September 10th,2011 with no said particular location. The ad says it could be Boston or could be Cambridge. At any rate, the line up looks pretty good. Wu Tang will be in the buildin’ so I figured that I ‘d put you on to it:

Ghostface
Black Moon
Black Star
Masta Killa
Mobb Deep
Nas
Raekwon
Childish Gambino
Cypress Hill
Erykah Badu
Immortal Technique
Lauryn Hill
Mac Miller
Random Axe
Slaughterhouse
Souls of Mischief