Bourne Identity star Matt Damon has revealed four little daughters love to slap his bald head. The Bourne Identity star shaved his head for his role in new movie Elysium. "My kids love to slap my bald head," says Matt. "It's kind of become like a go-to joke. It's something we do a lot. Even I give it a slap from time-to-time just to get a laugh. I'm going to miss it if my hair ever grows back!"