It's a
coin that's worth one
dollar.
Clearly the most evil thing ever conjured up by humankind. People look at you funny when you try to spend them, and they look just like quarters. Vending machines also won't take the damn things, and they tend to accumulate like dust.
The only redeeming quality this coin has is that it's somewhat rare. They're hard to find, so getting one is special. Until you find out that the stamp machine at the post office distributes them as change. Then you can pay for a $4.95 book of stamps with a twenty and get a shitload of them.