MSNBC host Rachel Maddow is about as even-tempered as cable personalities get. She avoids the pugilistic nature of her colleague, Keith Olbermann, preferring wonky but reasoned political analysis. Though Maddow has occasionally been drawn into sharp exchanges (see her takedown of Glenn Beck), she generally avoids overheated confrontations.

So what does it take to get under Maddow's skin? A false rumor from Massachusetts senator Scott Brown, who claimed in a fundraising letter that Maddow was planning to run against him in 2012. Flabbergasted, Maddow took to her own guest chair to refute Brown, protesting: "I have the best job in the world. I'm not running for office. Nobody's asked me to run for office."

When Brown reiterated his rumor on a Massachusetts radio show and added "bring her on," Maddow got tired of playing nice and took the safety off her big guns. First, she responded to Brown directly, asking "Bring what on??" In the same segment, she recorded a fake robocall to the people of Massachusetts. "I'm his constituent, and he didn't even have the decency to call and ask me if what he was saying is true before he smeared me around the country to raise money for himself," she declared.

Maddow didn't stop there. Instead, she diversified her media barrage, taking out a full-page ad in the Boston Globe rebuking Brown for trying "to scare donors into giving him more money." Not yet finished, Maddow moved into satire, mocking Brown with a fake campaign ad on her show.

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Maddow still has one more show this week. No word on whether she's hung a Scott Brown piñata on her set.

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