The fourth episode of the 25th series of Never Mind the Buzzcocks (broadcast on 24 October 2011) had the magician Dynamo in Noels team. Dynamo performed some illusions on screen, but aside from the very visual tricks, he did one that wasn't even mentioned during the episode.
A panel show is recorded live on tape. Multiple cameras record the action happening from the beginning until the end. This means there is almost no chance of a continuity error happening. Unless you're dealing with a magician. When the episode starts, Dynamo is wearing a T-shirt of Phil Jupitus (the captain of the opposing team). There is a video of him online saying how much of a fan of Phil Jupitus he is.
After a while he's wearing a T-shirt of Noel Fielding, his team captain.
It's not shown when he changes it and it's never even mentioned. It's just a neat little trick happening in the background.
As a sidenote: I know that live on tape shows are not always filmed from beginning to end in one go. When something goes wrong and the taping needs to stop, they will pick up from a few moments before. It's possible for continuity errors to happen in that case.