Faviki is a social bookmarking tool that lets you use Wikipedia concepts as tags. Faviki allows you to keep your own tags and connect them to common, universal concepts from the world's largest collection of knowledge!
C. Cattuto, D. Benz, A. Hotho, and G. Stumme. The Semantic Web -- ISWC 2008: 7th International Semantic Web Conference, Karlsruhe, Germany, volume 5318 of Lecture Notes in Computer Science, Springer, Berlin, (2008)
M. Zhou, S. Bao, X. Wu, and Y. Yu. Proceedings of the 6th International The Semantic Web and 2Nd Asian Conference on Asian Semantic Web Conference, page 680--693. Berlin, Heidelberg, Springer-Verlag, (2007)