I would like to be a fly...

[katikat]

... and just sit on the wall and watch these guys when they goof around.

Cyn: Well, the fans have been bugging Eric Kripke for a body swap episode. So maybe one of the Winchester boys could change places with Castiel.

Misha: Oh, that would be fun. That would be a great opportunity to mock one another.

Cyn: If you made the switch, which of the boys would be easiest for you to mock... or shall we say, imitate?

Misha: (laughs) Jared and Jensen have both given me a lot of material to work with on the mocking, so it’s hard to say, probably a toss up. It would be more absurd for me to play Jared just because he seems so gigantic to me. He’s just so tall that there’s something in that that would be inherently, physically different. So, I think that that would probably be the most fun to do.

Source: Ten Minutes with Supernatural's Misha Collins.