Jay-Z and Beyonce

Jay-Z and Beyonce, who have yet to open up publicly about their two-and-a-half year romance ("We don't play with our relationship," says the rapper, 35), keep their partnership on solid ground by supporting each other's endeavors. Most recently Jay-Z attended the Academy Awards to cheer on his girlfriend, 23, as she sang three of the five Best Song nominees (and changed outfits five times).