There are tens of thousands of such sites.
The creators of this spam are able to get 5 millions of traffic on 5 days old domains.
They are able to index millions of pages in a single day.
They interlinking the domains on every single page.
All domains are expired, dropped and freshly registered.
It is temporary - the domains are getting Google penalty in a week or two.
It is working on subdomains on many EU country-level TLDs - .de, .es, .fr, .it, .pl, etc.
They found a huge loophole in Google algorithm and making from it millions per day.
