Its a tricky thing to do as the potential for link-spam is very high. All one needs to do to rank his/her site high is to link to some authoritative/reputed site. Edit: One apparent fix is to assign smaller scores to outlinks as compared to inlinks. Even this is easy to game by setting up numerous pages to harvest outlink score, and then direct it to a page as an inlink.
Edit: Erm anything wrong with my comment ? This got voted down to -1.
As a graduate student I look into algorithms like these for ranking web pages.
This was with reference to dead-end websites and awarding a Pagerank like scores based on what my site points to (in addition to those who point to me)