Imagine this scenario in a realworld cardroom: You make a river bet, get called, and turn over your hand. Your opponent mucks his cards without showing, but curiosity gets the best of you, so you reach into the muck and peek at his discards. How many times do you think you could do this before they threw your sorry, angle-shooting ass out of the casino? Yet online you can do it all day, every day, and if you're not aware of it you should be. Every online poker site has a handy little feature called instant hand histories. At the click of a button, a little text box pops up or, on some sites, a graphic clone of the hand just played. There, much to your delight, you will see the cards of everyone who called the final bet, whether they voluntarily showed their hands or not. Likewise, if everyone checked on the river, everyone's cards will be laid naked to the world in the instant hand history.

This tool is so massively useful, it's sometimes worth not betting on the river, just to see what the other guy had. Suppose you make a raise up front with, let's say, pocket eights. You get reraised from 'round back, but the flop comes so scary, perhaps three to a royal flush, that both you and your foe are frozen into inaction. By the time you get to the river, you're pretty sure that if you bet he'll fold, and if the pot's big enough to be worth winning, of course you'll bet. But suppose both you and your foe's money is very deep (or you're in the early rounds of a sitngo, when chips are cheap.) If you check, and he checks behind you, your hand will be revealed first and if you have him beat his will go in the muck. But it'll still be there in the hand history, and a click of a button will reveal it to you. Why that lying sack of sushi! He reraised with 7-8 suited! Well! Well, indeed. That's a thing worth knowing. I find that instant hand histories are indispensable in match play, where I'm concerned with the betting patterns of just a single opponent, and it's well worthwhile to know whether he considers A-x a raising hand, whether he likes to drag his monsters and, most crucially, whether he'll call with cheese. Instant hand histories give me access to this information and, as noted above, it's sometimes worthwhile just to check it down at the river for the sake of seeing what he's got. It's amazing how quickly the picture comes clear.

Of course my picture is equally being revealed, assuming my foe is smart enough to click the hand history button, and why would I assume otherwise? For this reason, I'll sometimes make small river bets I wouldn't otherwise bet. Say I don't want it known that I raised preflop with utter cheese but we get to the river without much further action. At this point I may know that the only way to keep my hand a secret is to bet if he checks, and hope he folds. If I bet and I'm called, yes I lose some chips, but I don't give away any extra information since if he had checked and I'd checked behind him, he could have that information through hand history anyhow.

Think about all the times you've said to yourself, "Damn, I wish I knew what that guy had." Thanks to instant hand histories, a lot of times you can know. All it takes is remembering to peek.