Penn Badgley and Milo Ventimiglia
Chace and Ed asked their Gossip Girl costar if he wanted to live with them too, but he already had his own famous roommate in Milo Ventimiglia. The This Is Us star was 28 at the time and would let an 18-year-old Penn "borrow his ID to get into bars." In 2010, he told Bullett, "I've still got it somewhere." P.S. That must have been one hot household.