I stabled over the web site of TopPayingKeyword.com today.
There are a lot of companies that offers keyword research tools, to help bid on the right keyword in Google. At first look I thought this is just another one of them, but it appears they offer something completely different.
When you put Google Adsense advertisements in your site, you share the revenue of every click with Google. Advertisements with higher CPC/CPM will get you and Google more money.
Now, when advertisers buy keywords, some of the keywords are more expensive than others. Following this logic, advertisements that shows up near this keywords in a site are more expensive, thus generating more money to you (the publisher) from every user click.
So TopPayingKeywords actually help you determine what key words you should use in your site content as much as you can, in order to make Google show more expensive advertisements.
Don't get me wrong, personally I don't believe in this system. I think that in the long run, good content will bring more users which will translate into higher revenues.
Still, their approach make you think on how Google AdSense works, and if advertisers really gets what they should for their money.