According to Cringely, BP has purchased a lot of ad words about their oil spill. Apparently they're spending over $10,000 a day trying to change the discussion in their favor.
So apparently every time you write in your blog about the oil spill, BP gives Google a little more money. But... if you the click on the ads, then it costs Big Profits even more. And people who have websites with Google ads (like this one) will make some money.
So look around... if you see BP ads, click on them. And if you end up on BP's site, tell them to stop wasting money and time on the internet and figure out how to fix the oil spill before the hurricanes pick it up and start coating the land (and very poor people's homes).