This activity reinforces the rules for affirmative informal commands in Spanish.
Students divide into teams, and each time receives a mini-whiteboard and marker (or pen and paper). I write the SPANISH translation of an English-language song on the board, and teams can win a point by being the first to guess the English song it's referring to. I tried to pick only songs that they'd most likely know.
I've used this in the classroom with great results.