This week, the Justice Department fined Exxon Mobil $6.1 million after the energy giant violated an agreement to cut air pollution at four of its refineries, including two in Texas and one in Louisiana. The fine comes on the heels of a court order this summer that the company pay $507 million in punitive damages for the 1989 Exxon Valdez oil spill.

Before you start to feel to sorry for Exxon, though, let's put the fine in perspective. Exxon Mobil's 2008 profits had already topped $38 billion by October, thanks to big windfalls from skyrocketing oil and gas prices.

That works out to about $139 million in profits a day, or $5.8 million in profits an hour -- an amount close to the fine they're paying for polluting the air.

As for that $507 million in punitive damages Exxon paid for the Valdez disaster: That's down from the $5 billion a jury in Anchorage, Alaska originally asked for against Exxon in 1994 -- which was lowered to $2.5 billion by an appeals court and eventually down to $507 million by the U.S. Supreme Court in 2008.

At their 2008 windfall levels, Exxon was able to cover the Valdez fine with just the profits they earned in about three and a half days.