Saw two new Google Adsense ads experiments on my blog today. 
Had seen those type of ads mentioned in other blogs before but this is the first time I saw them. 
The first type of Google Adsense ad shows a list of products (related to the post) available at eBay for sale. Look at the screenshot on the right. This ad was appearing on this post of mine. No “Ads By Google” on this ad. I think this ad will increase CTR.
The second one is the ad which is displaying a “Show More link” below the ads. On clicking the link I was taken to a page with more contextual ads.
Have you seen these ads sometime in your blog ?