Really surprised this thread was brought back from the dead after a year.
Either way besides the chain-bet website there aren't that many. And honestly somebody really should make one as a smart contract for ETHEREUM.
With bitcoin due to the VERY SLOW confirmation times and VERY HIGH transaction fees you are better off using a different currency.
This would be very easy to program as a smart contract on ETH and everybody can verify looking at the source that they aren't being cheated.
Ethereum blockchain is much different from Bitcoin blockchain. They have a concept of uncle blocks as orphaning happens every now & then. If chain-bet is as is implemented in Ethereum, then miners may influence the result in their favour. It is possible to do it with lot of confirmations on Ethereum blockchain, but that would be same as doing it on Bitcoin blockchain.