Or maybe you like a long shot. In that case, the site will take your wager on whether the Earth will run out of oil by 2050. Pessimists could make out nicely if the wells dry up in few years with a $100 bet earning $1,000. Even longer odds are on gas prices going lower. If scientists announce tomorrow a $4 gadget allowing your car to run on household waste (Mr. Fusion, anyone?) and the average national gas price plummets to less than $1 a gallon, your $100 bet earns you $15,000. That's a lot of cheap beer and banana peels for your future Delorean.