The best ever example I've seen of the Prisoners dilemma worked like this:
Two people have "won" $50,000. They then have to sit down, converse, and secretly submit whether they want to cooperate or betray. If you both cooperate, you each get $25k. If one of you betrays, he gets the whole thing. Usually, no matter what you plan to do, you want to convince the other person to cooperate, because if you both betray, neither of you get anything (for psychological reasons, this is still the Prisoner's Dilemma - there is inherent value in insuring the other person gets nothing for betraying you. But it made it more likely for people to pick cooperate)
These two people sit down. One of them opens up the conversation by being very straightforward.
"I am going to betray you."
The other person is taken aback. Asks wtf he was doing.
"I am going to betray you. It's pretty simple. There's nothing you can do to change the outcome of my vote. But there is this - if you cooperate, I will give you half the winnings after the show. This guarantees that you can't betray me. You still have your choice - whether to trust me or not - but mine is simple. There is no better situation for me than betraying. So I am 100% absolutely positively going to betray you. Saying this is my gesture of trust - I am honest. I am being 100% honest with you right now, and am going to give you the other half if you choose to cooperate. I am not playing deceptively, but I am not going to play the game in a way where I'm going to lose, so I am going to betray."
Everyone is riveted, the host too. The other guy says "So my only chance is to cooperate and hope you give me half?"
"Yes."
No one can believe this. In a great many iterations, no one had ever taken the stance that they were DEFINITELY going to betray.
They submit their votes... and both players have submitted "cooperate". Turns out the guy wasn't being truthful at all. But it's probably the best lie I've ever seen.
Man, I wish I could remember the name of the show...