I am obviously a sucka for lists, there's one with 400+ links. I am doing everything humanly possible to try, review (reviews are on the way) and categorize the gazillion startups and old hags alike. I have updated the so called complete list with some cool thumbs (check it out).
B. Krause, R. Jäschke, A. Hotho, and G. Stumme. HT '08: Proceedings of the nineteenth ACM conference on Hypertext and hypermedia, page 157--166. New York, NY, USA, ACM, (2008)