It only happens once a year, but last night, something magical happened: a ballroom full of important people in Washington got something done.

What did they do? They spent an evening drinking and making fun of how important they are. And as usual, it was pretty hilarious.

The White House Correspondents' Association's annual dinner is a highlight on Washington's social calendar, and meriting an invitation is in itself almost newsworthy. Every year, congressmen, US senators, supreme court justices and members of the media mingle over dinner and listen to the President deliver a (usually) gut-splitting roast of himself and his own administration.

This year, President Obama appeared on stage with his own personal "anger translator," someone who seemed to cut through the president's cool-as-a-cucumber demeanor.

While some dinners are funnier than others, the WHCD event doesn't look like it's going anywhere soon. Every president since Eisenhower has appeared in person - every single year - and the jokes just keep getting better and better.

One of the best in recent memory is when President George W. Bush appeared with Steve Bridges, a professional George W. Bush impersonator. Say it with me now: "nuclear proliferation."