Well there are quite a few traffic exchange sites, that is basically what this amounts to if I am thinking of the same thing.
http://www.spottt.com/ that's it... i don't think it's been very successful though, as they have a lot of weird rules. Its the closest thing to entrecard that i've seen
I have tried both and wasn't impressed. The participating sites that "drop cards" are usually spammy crap sites with no content and no relevance. While I think the concept is good, more development needs to be done in being able to allow or disallow certain criteria, categories etc. For now it's annoying to go check the site every time someone drops a card to see if it's worth keeping or not.
You could try the one that is selling some beer credits. honestly I don't even bother on suing them because I find out that the traffics that they are giving me are not clicking on my advertisement. I'm just using entrecard credits to promote my site on contest. It would be better if you would just do your SEO.