The Psychology of Con Men

My all-time favourite [short con] only makes the con artist a few dollars every time he does it, but I absolutely love it. These guys used to go door-to-door in the 1970s selling lightbulbs and they would offer to replace every single lightbulb in your house, so all your old lightbulbs would be replaced with a brand new lightbulb, and it would cost you, say $5, so a fraction of the cost of what new lightbulbs would cost.
The Psychology of Con Men