Ask HN: Can I write a recommendation engine for HN?

Simple item-based (hackers who upvoted this article also upvoted...) and/or user-based (hackers who upvoted similar articles to you, upvoted ... ) recommendations would be cool to see on HN, possibly as a way to access (relatively) older content that one might have missed. this assumes people are actually away from the site long enough to miss something -- unlikely. addicts!

I think as the user base of HN continues to grow this can help keep things from approaching the LCD.