Faviki is a social bookmarking tool that allows you to tag webpages you want to remember using Wikipedia terms. This means that everybody uses the same names for tags from the world’s largest collection of knowledge
If the wikipedia ontology: dBwiki and the ontologies from Delicious, Digg and Diigo could be mashed up into a tagging facilitation tool that plugged into WordPress, Blogger, etc I’d use it. Would you?