I'm not sure if this has been posted before and I'm probably in a minority of people who think this is funny...but Iain Lee's prank calls to quiz channels just crack me up!
He phones up as someone called Tony, and regardless of what the quiz question involves his answer is always 'Ghostbusters 2'.
The first couple of times the presenters were having a laugh with him. Each time he phones though the presenters get wise to who it is and eventually get pissed off with him and expose who 'Tony' really is. He hasn't phoned back since!