The United States had more unprovoked shark attacks (29) than any other country in 2011. Florida had more (11) than any other state. And Volusia County had the most (3) in Florida, according to the International Shark Attack File at the Florida Museum of Natural History. Still, shark attacks have decreased in recent years, in part, because the recession has reduced waterside tourism. And attacks remain rare. Lightning kills more people (51) in the United States each year.

How did the Chicago bus drivers rip off Uncle Sam?

The Chicago Transit Authority over-billed the federal government for as much as $150 million in subsidies since 1982, taxpayer advocate Cause of Action said. The CTA was getting up to $5 million a year too much because it improperly charged the government for the miles traveled by empty buses, so-called "deadheads." The problem was detected in 2007, but continued. The government will not try to recoup the money, federal officials said.

What is a "Frankenstorm?"

That's what government weather forecasters are calling the potential confluence of a Caribbean hurricane and a Midwestern winter storm that could collide over the East Coast, including the D.C. area, this weekend. Heavy rains and snow could hit anywhere from Norfolk to Boston, forecasters said. In the worst-case scenario, the storm could cause $1 billion in damage.