I came across this gem:

Alessandro "Derek" Del Piero is threatening to sue Facebook over a fake page with his name on with links to a N@zi propaganda group. His representatives wish to make it clear Del Piero has never had a profile on Facebook, because he has proper friends and a life.
Quite!

On a more serious note:

Fake profiles on social networking websites are becoming a bigger problem, with numerous incidents of abuse on sites such as Facebook and Twitter over recent months, and no signs of anything approaching a strategy to combat the problem.
I can smell legislation in this area fairly soon.............