Martha Raddatz starts with a warning about cellphones in the audience. Supposedly, she was at a White House briefing when her phone rang — and her son had sweetly changed her ringtone to Chamillionaire's "Ridin' Dirty." For those who want to better appreciate Raddatz's son's musical tastes, here's a link to that song. (Warning: Probably NSFW, if like us, you are still at work).