I wonder why we only count the number of citations our papers get.  We should also count the citations of all of the papers that cite you, since they were somehow related.  Maybe as the degree of separation increases the weight of each citation in that layer changes.  Would be interesting.  Also, maybe included in the weight calculation is the distance from the related paper in terms of subject area (like astro physics and psychology are light years apart in similarity but if your paper was influential enough it might be cited by someone in psychology and that would imply importance…).