Each player gets one card face down and place a bet. The remaining cards are flipped over one by one until a card is turned over which matches one of the players. The player whose card is matched wins the pot.
Stupid, right? (It isn't clear whether the deck is reshuffled. Slightly more interesting if it is not.)
Let's see if we can make it more worthwhile with a (two-person) lowball variant:
1. Each player gets one card face down.
2. The cards are flipped over one by one. The player whose matching card is flipped over first loses. But he is not obligated to disclose this.
3. After each card, either player may request that the other player turn over his card. If that card matches one of the already flipped cards, the requester wins the pot. Otherwise he immediately loses the pot. (Variant A: He is required to contribute to the pot and play starts with a shuffle and new deal. Variant B: Muck the face-up cards but continue with the same deck, dealing two new downcards, and reshuffle only when the deck is exhausted. Variant AB: both.)
Need to figure out what happens if both players request to see the cards simultaneously. Maybe it can be played with an alternating button to decide who shows first. :)