AMEX:UVXY   ProShares Trust Ultra VIX Short Term Futures ETF
Anyone who thinks it's a good idea to hold UVXY , you need to look at the long term charts. The decay on this is horrible.

You can however make a lot of money if the market tanks, but you need almost perfect timing. Not something I would hold unless I was sure the market's gonna tank.... at that point you might as well buy put options on stocks anyways,
Comment: As I was saying, you need absolutely perfect timing to make any money off this. It's for short term trading only. Day trade.... or couple of days at most