buckworks - 8:52 pm on Mar 10, 2010 (gmt 0)
I sold a site recently, and the process was that when they put down a deposit, I gave them access to copy the site to their own servers. But they didn't control of the domain name until their next payment was in my lawyer's hands.
I didn't have any clever code to protect, though. What made the site valuable was the backlinks so cloning my content wouldn't do them much good until they had the domain to go with it.