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If I had to guess, I would ray any variant of these keywords is definitely the most popular.
I am sure others can build on this list
I'm going to put together some AdSense sites about keywords that have high bids. It's like a license to print money! I'll tell all my friends and family around the country about it, but warn them NOT to click on the ads, even though any money I get from Google will be spent on their Christmas presents this December.
Then I'll go to the Webmasterworld AdSense forum and talk about what a great program this is, how I'm making more money than I thought I would. And also complain about how the EPC is lower than it was in the past.