If you do want to gamble, check out Keno, it's kind of like a state lottery. The odds are terrible and you will almost certainly lose every drawing, but you can generally bet as little as $1, the drawings happen around every 5 minutes (so you lose around $12 per hour), and you get free drinks while gambling there.
If you actually want to play something with the intention of maybe winning a little pocket change, go with blackjack after memorizing
Basic Strategy (a strategy based on math that minimizes your losses). Most casinos will even let you keep a copy of the chart on the table while you're playing since even with the odds mathematically minimized, they're still favorable to the house. And dealers will almost always honestly tell you what you should do (most of them have memorized the tables too), since their paycheck doesn't depend on you losing, but the possibility of you tipping them does depend on you winning. (Oh, and it's courtesy to tip the dealer a chip or two if you come out ahead.)
Also, if you gamble, make sure that you not only have a losing threshold ("If I'm down $100, I'm quitting!"), but a winning threshold as well ("If I'm
up $100, I'm quitting!"). The house really does have the advantage over the long haul, and they count on people being up and continuing to play until they lose it all, which they
will eventually do. If you don't have a winning threshold, you will inevitably lose. If you do have a winning threshold, then you might get out of there and actually be able to treat your friends to a nice steak dinner.