The only site that I used that and reminds me of HN is Perlmonks(.org). It never had any commercial ambitions and the quality has been maintained for a decade. There's tons of lessons to be learned from it. They use blind voting, have user levels, and the higher level users moderate. The community there is unbelievably awesome and it has a very similar feel to this site.

http://perlmonks.org/?node=PerlMonks%20FAQ