I'm a romance baiter.  I bait romance scammers.  These people are the scum that steal your heart and then your money.  I've been doing this for coming up to 3 years now, and have developed my own style to use with Instant Message baiting.
  
The character I use will have 2 "personalities" during the bait and will jump between them during the course of it.  Personality #1 is the one they first meet.  I'm nice, polite and very easy to get along with.  This is my passive character.  He/she will give the scammer what they want (within reason) and make them think they have an easy target.  Partway thru the bait, and without warning I morph into personality #2.  Personality #2 is the total opposite of #1.  

I can be as evil as I want to be when I'm #2, and frequently am.  I make crazy demands, discuss all manner of sexual practices in great detail and basically put the scammer (lad) on the defensive instead of the offensive. This is my aggressive character.  He/she (because I can be male or female in my baits) switches roles with the scammer.  I use every trick they use back at them at this point, from emotional blackmail to name calling.  Once I get what I want, I revert back to personality #1 for a few days and let them think they have the upper hand again after a slight bump in the road.  

I let them think they're just about to get the money when I change back to personality 2 and come at them all guns blazing.  Some back off and give up at this point, but some assume that if they can get over this problem then I'll revert again and they'll have the money.  These are the ones you want.  These ones will be putty in your hands.

Another trick I use, I call the olive branch/slap technique.  This works for getting a scammer to admit he's not really the person in the photos, from Mooseknuckle Point, Alabama.  All you have to do is slap them for lying and tell them you KNOW they're lying, then offer them the chance to redeem themselves by telling you the truth.  Let them know you won't be mad at them and would much rather they be honest.  When they still claim to be the person in the photos, repeat the process.  Slap, then offer them a chance.  Slap, then offer them a chance.  

If they still refuse then walk away for a day, telling them you want them to be honest when you speak to them next.  A lot will finally admit to a much closer version of the truth to you after this.  Still not the 100% truth, but it's a good start.