Video: Beyonce Knowles' Unintentional Nipple Slip When Rendering Deja Vu at Toronto Concert

From Youtube:

Beyonce's Top goes flying [picture below] during her performance of Deja Vu, makes funny faces after, and holds down her shirt/skirt/dress thingy in front of the ACC crowd in Toronto (which you can hear a few cheers after).

This is the second incident that happened to Beyonce during her recent performances. On July 24, the singer tumbled down stairs when she was in the middle of performing "Ring The Alarm" at a concert in Orlando, Florida.