PHOTOS: T-Pain, Lonely Island among celebs with mic-dropping sets at San Francisco's Clusterfest

SAN FRANCISCO (KGO) -- Thousands of people packed San Francisco's Civic Center area this weekend to see their favorite comedians and musicians at Clusterfest.

The Lonely Island, T-Pain, and Michael Bolton were among the musicians who delivered epic high-energy sets.

Click here for more information about the festival.