This is a new thing that flagged in my adsense account today and I hadn't heard of before. Matched Content units.
Basically you can run an adsense style unit for your own website, but it will display your content. So another way of trying to keep your pages sticky and traffic on your site.
There is no cost for it, and although they look like an adsense unit, there is no financial compensation if someone clicks on the "advert". They also don't count as one of the adsense units, so you can add one and not break Googles Terms of Service.
I've been having a play, the idea seems good, but its the fact they look like an adsenes unti that puts me off 
I tried one on the forum earlier as a test:
So above Trenas post was an adsense unit that is supposed to display relevant content, but only from this site.
I think on the forum it's a bit distracting so have turned it off, but have added one to our free listing pages on the directory. The below image is a link if you want to see it for real.
Jury's out, idea is sound, not so sure on the execution 
If you want to learn more: Google Matched Content - Adsense help
Anyone else playing with them or have any thoughts?
