I _used_ to be a huge fan of stumble-upon, but at some point they added too much algorithm to it, and something else behind the curtain went south and it just s

I _used_ to be a huge fan of stumble-upon, but at some point they added too much algorithm to it, and something else behind the curtain went south and it just started sucking. Edit: StumBleUpon was a browser plugin (optionally, you could also use their frameset version at least earlier on), that would try to learn your interests based on previous sites you liked/disliked.