Up and Down
This game is best for romantic couples, since it gets the players up close and very personal. Start by placing a ping pong ball at the bottom of the man's pant leg. The woman then races to move the ping pong ball up and down the other pant leg without using her hands. Teams race against each other to see who does it the quickest. A different take on the game that's suitable for a wider variety of players has the ball moving from one shirt sleeve to another.
Newlywed Game
Take inspiration from the famous 1970s couples-themed television show to spice up your party. The players take turns answering questions the way they think their partner would answer. Couples get points for right answers. One person plays the host and asks the questions. While one partner is answering questions, the other player waits in another room. When the first player is done answering, the absent member of the couple comes in, hears the questions and answers them. The host then reveals the first partner's answers to see if they match up. Have all the "second" players leave the room at once, while the "first" players answer the questions, then bring them all back at once for a group answer comparison.
Clothing Swap
For the clothing swap, you need a bunch of clothes, both men's and women's, in large sizes. At the beginning of the game, have each couple select an entire outfit, including tops, bottoms, accessories and shoes. Mix all the outfits together in one large pile. Players then rush at the start of the game to find all the pieces of their pre-selected outfits. Once they have everything together, they have to dress as quickly as possible. The first team to get both players dressed wins. The catch is that the players must dress in the opposite sex's clothing. In other words, the men must wear a woman's outfit and vice versa.
Egg Pass Game
The egg pass game requires players to get very close, in order to move an egg around between their bodies. At the beginning of the game, the couples place a hard-boiled egg between their lower backs. Once you give the "Go" command, they have to lower the egg to the ground without touching it with their hands. Either play the game simultaneously with all couples competing at once or individually. If you play individually, use a timer to determine the winner. If you're playing outdoors, preferably at a pool party where everyone is in bathing suits and can get hosed down, play with a raw egg for an added fun factor.