provably fair gambling sites?

[Chemistry1988]

^ Is that site freebitco.in? I never used and never will use it to gamble my bitcoin (actually I never consider it as a gambling site but only a faucet), because it has a terribly high 5% house edge.
As shown in your above post, it seems the site uses your IP as part of the server seed but not the nonce (the nonce for that particular bet is 37363).

EDIT: I have created an account to do a little bit testing just now. It appears that the server seed hash (with my IP appends) does match with the server seed hash given before the bet. But still there is no reason to gamble there with such a high house edge. I would suggest you to try some proper dice sites.