Is this implementable? enforceable?

Schwarzenegger signs bill requiring email addresses for filesharing

California governor Arnold Schwarzenneger -- a man who found considerable fame and fortune in Hollywood -- signed an MPAA-backed bill into law Tuesday that requires anyone sharing a file that goes to more than 10 people outside their immediate family to provide a valid email address and title of the work.

California file sharers who trade songs or films without providing an e- mail address will be guilty of a misdemeanor, under the first-in-the-nation measure that could make it easier for law enforcement to track down people who illegally download copyrighted material. The bill is the latest attempt by film and music trade associations to combat the hard-to-police use of file-sharing software. The signing was hailed by the bill's sponsor, the Motion Picture Association of America, whose president, Dan Glickman, noted in a statement that Schwarzenegger had "a unique understanding of the powerful impact of piracy.'' The governor remains a member of the Screen Actors Guild, which supported the bill.

Link
 
It's pretty easy to create and use an email address on a public computer making it relatively untraceable.