I read about his work a couple of years ago. He has come up with a good way to prevent a facial recognition algorithm getting "true positives", but I think to truly mess with The Man, how about my idea for a textile pattern to also generate lots of spurious "false positives": http://shacklemore.blogspot.com/2010/04/facial-recognition-camoflage.html
Hopefully, if enough people wore this fabric, any real-time facial recognition algorithm would start getting CPU bound, and limited by the speed of running hundreds of database queries against it's back-end database.
Cool - that could mean that spammers would start writing botnets that would also block government spam from landing on the computer, in case the user gets educated and figures out how to secure their computer.
I can imagine a new spam race where the government has to write ever more clever spam to get round the malware's rulebase!