LulzSec turncoat Hector Monsegnur (better known by the handle 'Sabu') was apparently arrested last month after impersonating an FBI agent, according to Gawker. Apparently he was approached by a police officer regarding an unrelated matter, but when the officer asked to see his ID, Sabu responded by saying, “My name is Boo. They call me Boo. Relax. I'm a federal agent. I am an agent of the federal government.” Yep.
Gawker speculates that the officer might have misheard 'Boo' for 'Sabu,' and they also propose that he was attempting to use his snitch status to get out of whatever trouble he was in. We would throw the idea out there that it's a possibility that Mr. Monsegnur may have been enjoying some very fine controlled substances at the time, but since he wasn't charged, we guess that he just says stuff like that.
Since he couldn't produce any kind of official ID, the officer contacted the FBI, who denied any relationship with Sabu. In the end he got slammed with a misdemeanor, second degree criminal impersonation. Chances are, though, that his snitch status will get him out of all those other serious charges he would normally be facing from the FBI. Go figure.