Been done a bunch of times, always failed.

Here's the latest, something called MidasCoin:  https://bitcointalk.org/index.php?topic=784286.300

They say they'll give you a set amount of gold per coin no matter what.  On Bittrex the price is crashing.  To meet their promise they'd have to buy extra gold and send it to people for worthless MidasCoins.  Good luck with that.