Where are the BEST hiphop shows/ clubs in Boston? What makes them better than the rest?

I'm really into hiphop and I wanted to find out what shows/ clubs are a MUST to visit/see while in Boston [obviously I'm not a native]? If you could also mention the general feel/atmosphere of the club, what's cool or not there[restrooms, bouncers, etc], specialties [drinks, nights, events, etc], and just whatever else I'm not likely to find in a travel guide ;-p Thanks in advance xxx