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always worries me when people ask that question...
I am always curious as an advertiser why you would want to know that information.
is it for analysis, or is it for creating content which show high value keywords in the PPC industry.
As an SEO I often wanted to know what the high priced keywords were. I'd create sites targeting those keywords, get the site ranked well then put a "this site is for sale sign" on it. I don't think it would suprise anyone to find that people paying $30 or more bucks per click are quite interested in sites that rank well for their expensive keywords.
Those sites sell themselves. Not quite sure why it worries you Shak.
Therefore SEO's will start to optimise their site to contain these "high paid" keywords which will mean the AdSense banners that will be displayed on that page will be bigger earners.
However I would not recommend creating a bunch of pages that are purely "high paid" keyword dense without proper content. Google likes real content.