Wilmer Valderrama and Demi Lovato
No, really, oppposites attract. Lovato is young and innocent and, as far as we know, hasn't dated anyone else famous. Valderrama is older and was hailed for years as Hollywood's biggest player; the guy has slept with Lindsay Lohan, Jennifer Love Hewitt and Mila Kunis, just to name a few!
Heidi Montag and Spencer Pratt
Remember Heidi Montag and Spencer Pratt? We try to forget them, too. But the former Hills stars always seemed far more into headline-making than lovemaking with each other. No one could have predicted they'd still be together.