I dunno, string him along with some bogus stories, try to get his personal contact info/address/anything else, don't let on that you know he's a scammer... I can't think of anything clever at the moment...hahaha ok ok, give me some ideas
419eater.com is a good place to get ideas for scammer baiting, the guy who runs the site loves messing with Nigerians.
Yeah, it's sad to see normal people in a depressed country resorting to these tactics just to survive. Some of them have been taught that this is a good way to make money.