Justin Bieber's latest prank involves balls.

Justin Bieber played Toronto earlier this week, and if there's one thing the 16-year-old pop sensation likes more than social networking, it's pranking.As seen on video, below, Bieber bombarded his opening act, brother band Burnham, with basket upon basket of balls. That scamp!Apparently it was all part of some sort of in-joke.Earlier this week, Burnham Tweeted that they pranked Biebz by cramming