The Roommate Switch : Suggest a menage-a-tois. The girl will recoil in disgust and tell you to get out. She later mentions it to the roommate who shows her sympathy, yet cannot help but be intrigued and flattered by the suggestion. Place a phone call when the girl is known to be out. Talk up the roommate and use humor and then invite to dinner. The original girl will tell the roommate to go ahead and date him. It can't fail (well, if you're George or Jerry, it can!)