Astley participated in a rickrolling himself, at the Macy's Thanksgiving parade a few years ago. He popped out of a float in the middle of another musical performance and started singing Never Gonna Give You Up. It was a staged stunt, with a canned background track ready to go, and the TV announcers obviously feigning surprise.

http://www.youtube.com/watch?v=wL-hNMJvcyI