I think social bookmarking sites like del.icio.us (which I use a lot) are wonderful. But I’ve rarely met someone in person who actually uses them, let alone who is aware of them or what they are. This video explains social bookmarking (and specifically del.icio.us) in plain English. Well worth a look if you’ve been wondering what all the fuss is about.
(Also check out other videos by the same author, covering things such as RSS and Wikis.)