Race To The Bottom
I was at a local mall when I saw one of those spiral wishing wells. If you don't know what I'm talking about, here's some video:
This is literally throwing your money away. But then, I guess that's what wishing wells are all about. And, to be fair, you do get a bit of a show--more than what a regular wishing well, or a fountain, provide.
There's a little card there suggesting you try different coins to see if they go down at different rates. I don't think so. I'm willing to try a penny--after all, they're worthless--but I'll keep the quarters. And dimes. And even nickels. They disappear quickly enough without any help.