Using Special Bitcoin Wallets to Trade Derivatives (Futures)

Do you think it would be possible to do Derivatives Wallets? The idea would be that you could do futures by using these wallets. Imagine a wallet with two 'pockets'. Each pocket
has the address of a different bitcoin wallet. So let's say the price of a barrel of oil today is $100 and I offer to 'sell' you a barrel of oil for $100 a month from now. We both put $100 in the Futures Wallet and enter the date the contract matures and the commodity that is being traded, the wallet is now locked until that date. The wallet is linked to a trusted market feed like the New York Stock Exchange; when the contract matures the difference is automatically sent to the specified address for that pocket. There wouldn't be much money to make aside from a bit of advertising on the site where people can download the wallets (I suppose it would be safest to keep the wallets on a third-party server as well) but it would be good for society in that brokers could be eliminated (no more transaction fees), and of course it would be good for bitcoin.