Thanks ! Didn't know that one, but seems to be this.

Doesn't seem to really take off - 6000 users in France after 3 years of operations (data from a french article a year ago, not sure if reliable), and their FB page has last posts about a year ago too - I would say it's dead now.

I'm gonna take a look why it didn't take off.

Btw, the same idea in UK - Cookisto.

I didn't knew about them. They seem to be catering EU, there is nothing I came across in US.