Biggest Reality Show Catfights
Lauren Conrad and Heidi Montag, The Hills
The former friends became archenemies after Conrad accused Montag and her boyfriend Spencer Pratt of spreading a rumor that she had a sex tape with her ex, Jason Wahler. The two have rarely spoken since their famous confrontation -- when L.C. shouts, "You know what you did!" -- but seem to put the past behind them in the MTV show's upcoming fifth season.