President Barack Obama offered a bit of wisdom to a ballroom filled with celebrities, political insiders, and journalists: There are a few things in life harder to find and more important to keep than love. "Well, love and a birth certificate," he quipped at last night's black-tie White House Correspondents' Association dinner. The president out-joked emcee Jay Leno, reports Politico, who generally played it safer than, say, Stephen Colbert.