Quote from: DannyHamilton on October 18, 2012, 05:48:17 PM

Quote from: dooglus on October 18, 2012, 03:29:44 PM

* play on a site which allows you to place bets against other players, rather than against the house. spot good value bets and profit from them. . .

I believe that this example is called "arbitrage" and is occasionally used in sports betting (or other gambling where the payoff odds on the same event can differ between multiple bookmakers).

I think if you're placing two complimentary bets which cancel each other out, leaving you a guaranteed profit, that's arbitrage. If you find a site that's offering a 10-1 payout for an event which you are pretty sure will happen around 50% of the time, that's not arbitrage; that's just taking advantage of someone estimating the true odds incorrectly.