I’m also a fan of William Kentridge. I can’t claim to have seen a lot of his work, but was very taken with a small exhibition of it at the Met a couple of years ago. Now he’s collaborated on a production of Mozart’s "The Magic Flute." Oh, to be in New York and have the opportunity to see this!
You don’t have to limit your collaborations to other visual artists. What can you cook up with musicians, writers, poets, and dancers? Those collaborations all have buzz appeal.