it's possible to create a booking system using Bitcoin.
The value of Q could come from a trusted 3rd party sports outcome publishing service. For instance you have a special authority that publishes sports outcomes in a known format, RSA signed, and they are known to be reliable. It wouldn't be hard to do for every major sport.
ex.
you want to bet 100BTC that Mets will win vs. Cubs on June 9th, 2013
"METS(6/9/2013)-WIN" is published and signed by the Authority if Mets win. "CUBS(6/9/2013)-WIN" is published and signed by the Authority if Cubs win.
Then a TX is created with two inputs, the STAKE(coming from the betters account) and the WINNINGS(coming from the bookie)
The scriptPubKey then checks to see if the signature for the win-code is correct, if so releases the funds to the better.
Another TX is created with one input, the STAKE(coming from the betters account)
The scriptPubKey then single checks for a signed win-code for "CUBS(6/9/2013)-WIN", if so released funds to the house.
Thus the authority only signs codes according to the sports outcome. If Mets win, then there is no signed "CUBS(6/9/2013)-WIN" ever in existence, only a signed "METS(6/9/2013)-WIN" which allows the better to redeem his winnings.
It might be possible to do this with ONE transaction, but I'm not completely sure.
You could create similar scenarios for political outcomes. Thus all you need to do is create a special service that publishes this information and these betting transactions could be created. It would require practically no technology, you could do it with command line Bitcoind, GPG and Google Docs.
-bm
That would be a very clever system indeed. It's along the lines of the idea of contracts championed by Mike Hearn (
https://en.bitcoin.it/wiki/Contracts#Example_4:_Using_external_state), which is currently under development. It's mind-blowing in itself, but difficult to say when it will be ready for testing/general use.
Some kind of service would need to be built around it to facilitate the matching of bettors, and "the oracle" would need to be fed regularly with event outcomes by a trusted party.
there are distinct advantages to this 'bookie' system.
bets are irreversible, cannot be voided.
the bookie and gambler can be totally anonymous.
gambler does not need to contact bookie to redeem winnings, it is automatically redeemable when the codes are published.
I see the same advantages of such a system.
The system I have in mind is a little more primitive, however, and works with existing Bitcoin features. Easier to explain by example - I can try setting up an example and running it here on the forum, anybody know of any upcoming events that would be fun to predict?
