When a player is dealt a card face-up that matches any card the player has already been dealt face-up, then the next card dealt from the deck is wild in all players' hands. For example, Player #1 has a Two and a Five showing; Player #1 is dealt another Two face-up; the next card dealt to Player #2 is a Jack; Jacks are now wild in every players' hand.
Along the same lines as Follow the Queen, when another player pairs up later in the game, the card that was the wild card is replaced by the next card dealt face-up. The old wild card is no longer wild. Also like in Follow the Queen, if the final card dealt face-up pairs up for that player, then there is NO wild card, as there are no more cards to be dealt face-up.
We suggests for more variety, that whenever a card is dealt face-up that matches ANY other card that has been dealt face-up to the same player or a different one, that the next card dealt face-up be wild.