Has there ever been an attempt to 'Pandorafy' Reddit?

Pandora is a website that makes customized music playlists based on your likes and dislikes. It is my understanding that it goes through your iTunes library and creates a profile of music that you like then uses your choices to suggest new music that you might like by comparing your profile with users with similar tastes.

Note: I live outside the US, so it doesn't work for me. This is basically how I understand this to work. I heard about it from a recent Freakonomics podcast.

How does this apply to Reddit? I am wondering if there has ever been an attempt to use upvote and downvote data to enhance Reddit in a similar way to Pandora. It seems like the signal to noise on Reddit is inexorably creeping more to noise. Implementing something like this might be a way to make Reddit a better experience. Has this ever been discussed before or considered for the future of Reddit?