recording studio scenes in movies and on tv

I just figured something, in all kinds of "American idol" talent type shows people are asked to sing acapella. Or in tv shows where they follow musicians into the studio etc.

These are often just little bits and pieces, but sometimes that’s all you need.

Chances are it’ll be an acpella that can’t be found elsewhere.

Right now I sampled a piece from a movie about ian curtis, from Joy Division, there’s some acapella from him in there, could be the actor singing it aswell, but it’s sounds good…

So, any ideas? particular episodes/movies /shows you guys think you can find these juicy bits in?