Dondon,

As I once mentioned before on here if you can you should buy WTI and sell Brent. They can not and will not maintain this upside down differential. As soon as they return to their correct relationship with WTI one or two bucks above Brent, you are in the money. You don't care if oil price goes up or down, it's easy money. The only thing you need to watch out for are the margin calls if the difference goes a lot further (highly unlikely at the current $10). In this case you need to maintain quite a large surplus in your account to be safe. Interest payments are negligable in the whole scheme of things so no need to worry about those.

OR if you have a rather large tank in your back garden you can buy Jan and sell Feb futures for an $8 gain.

Den