In a conversation between Chris Evans and Chris Hemsworth, the former says he could possibly cameo as Captain America in the latter's new Thor movie.
"[Chris] Hemsworth and I even talked about that. I would love to do a little thing in Thor 2. It is obviously going to be tricky trying to work out the plot, the reason why I am not there to help him, and why he is not there to help me. But the best thing about Marvel is that, like I said, the movies were so good and we had such a good time making them."