Lupe Fiasco is a true lyrical MC who won't let any performance hiccups interfere with his ability to get his bars off and put on a show.  In the middle of performing his "Mission" single at the SKEE Live show, Lupe got so caught up in the music that he wound up falling off of the stage.  He lost his balance after he began jumping around while rapping and tripped on one of the speakers, falling into the crowd.  Luckily, he landed safely on his feet and jumped right back onto the stage and continued with his show.  

Lupe wasn't at all affected by the fall, and he began freestyling about it shortly after.  Check out Lupe's freestyle comeback in the above slide.