Mine is to meet another couple and have our wives agree to wrestle. We'd rent a boxing ring for the night, and meet there privately to have the match. Our wives would wrestle a fall, and then come back to their corners to get worked on by their man, glaring at their rival across the ring.
It would start off as straight wrestling for submissions, but as the match progressed, it would escalate. A bikini top gets ripped off, a bottom comes off, and as they wrestle, they slowly start cheating (say a punch to the gut). Eventually, it reaches a head, and they agree to wrestle the final fall no rules.
My wife would finally win the match, and then stand in triumph with one foot on her defeated opponent's breasts.