For a short(?) but wonderful period of time it was possible to blacklist sites from your Google search results. As I recall Google moved this functionality into the Chrome browser several years ago.
When it was still available as an account setting I used it to filter out the awful "resources" like expertsexchange and that one Oracle consultant site with the hilarious pictures. When I see Quora results I long for that feature to be returned.
I remember that one because of the offer to learn Oracle during a cruise, complete with the important part "Convince the boss" : http://www.dba-oracle.com/BC_cruise.htm
When it was still available as an account setting I used it to filter out the awful "resources" like expertsexchange and that one Oracle consultant site with the hilarious pictures. When I see Quora results I long for that feature to be returned.