It doesn't take much for Justin Bieber to make fans go crazy in concert. His mere appearance does it every time.
But the 17-year old really had audience members screaming during a tour stop this week when he asked what single they wanted to hear. Between shrieks for "Baby,' Justin broke into a couple quick covers.
He sampled "Friday" by Rebecca Black and then "Baby One More Time" by Britney Spears. Eventually, Justin gave in to his supporters' demands, of course. Watch the fun unfold now: