If the guys are getting together, nothing says "I'm so bad" better than eating a jalapeno or habanero pepper without whining. If you think your friends have what it takes (and even if you don't), pick up an assortment of pickled or fresh hot peppers and commence to testing your tolerance for pain. Actually, the heat is in the pepper's whitish veins and seeds, so remove them first if you want to keep the proceedings civilized.
There are some cautions we should mention here: If things get too hot, water isn't a heat quencher. Try downing milk instead. Always wear latex or rubber gloves when handling hot peppers, too. The juice can be absorbed into your skin and transferred to other tender parts of your body, like your eyes, if you're not careful. Never play this game with children, and avoid biting off more than you can chew, literally. Try a small bite first, and abort the plan if visions of fire extinguishers flash before your eyes.