There was a great story on This American Life in September about a group of "Scambaiters" who run an elaborate con on some Nigerian scammers.
If you get a chance, listen to Act 1 "Hanging in Chad" on episode 363. Click on the full episode button to the left of the story. Hilarious!
http://www.thislife.org/Radio_Episode.aspx?sched=1260
"Three guys who go by the names Professor So and So, Jojobean and YeaWhatever spend part of each day running elaborate cons on Internet scammers. They consider themselves enforcers of justice, even after they send a man 1400 miles from home, to the least safe place they can bait him: the border of Darfur. The three self-made enforcers tell Ira their story."