A poker cheat that lets you win twice in a row, AND punk your friend at the same time!
Effect: In a totally fair, completely simple contest of "face up draw poker," the Scammer wins not one, but TWO beers off his mark.
Method: Start off with some smack talk. "You suck at poker." "You got no poker face! You couldn't win if your life depended on it." ...and then lay down the real challenge: "You're so terrible, you couldn't beat me in a round of draw poker even if we handpicked our cards from a face up deck!" I recommend making your bet totally irresistible. Say your $20 up against just one free beer. The spread is big enough, and the reward so tempting, you'll usually get them to go for it.
When they do, reiterate the rules: you'll be playing a completely normal round of draw poker, with the exception that instead of dealing cards out randomly, you'll each get to pick your hands out of the deck. And since you're such a nice guy, you'll even let him go first.
Odds are, he'll go straight for a royal flush. You do the same. Ask him if he wants to discard any cards, or stand pat where he is (he'll likely want to stay put). Once it's clear the round ended in a tie, remind him of the rules of the bet: even playing with a face up deck, you STILL couldn't beat me... and since you TIED, he didn't beat you, and owes you a free beer.
This will usually annoy your mark. He'll call shenanigans on your verbal trickery and want to renege on the bet. Offer him an even better solution: "I'll bet you double-or-nothing that if we played again, under the EXACT SAME set of rules, I'd beat you this time!"
Hopefully this will pique his interest and rope him into a second round.
Once you begin, off-handedly comment that since he went first last time, you go first this time (again, just following the regular rules of play). For your first round, pull out all four tens and an Ace. This will probably raise an eyebrow, and he'll pull out either a straight flush or a higher four of a kind (he can't pull out a royal flush, since you've nabbed all the tens). In either case, ask him (just as you did before) if he'd like to discard anything (odds are he will not).
...at which point you decide that yes, you would like to discard three of your tens, keeping only the ten and ace of the same suit. And finally, pull out the jack, queen and king of the same suit, giving you the coveted Royal Flush and TWO free beers.