I've had fun giving this a try. I've already tagged several of my favorite websites, and I will definitely be adding more. I have a plethora of bookmarks on my Firefox browser, and while they are all organized by folders, I think del.icio.us could help me even more. And it will also help to have all the same bookmarks available whether I'm on my laptop, desktop PC, or work PC.
I think this tool could be useful to librarians. Usually when we find a useful website for a particular school project or some other hot topic, we go around to each Info Desk PC and create a bookmark in Internet Explorer. However, if we set up a del.ici.ous account for our department, we wouldn't have to add a bookmark to each PC's browser. We could just tag the site under our del.icio.us account, and make it available to all department librarians in an instant. And that's just one of the possible timesavers del.ici.ous could provide.
On a more personal level, this tool could have been useful to me when I was working on my Bachelor's degree. I kind of wish I knew about it then, as it would have been great to have at my fingertips when working on various research papers. It would have been especially helpful, too, because I took most of my classes online and had to keep track of a lot of links provided by my professors. Well, at least now I'm in the know and can use this tool for graduate school!
While clicking on sites tagged by other users, I found something relevant to us here in library-world. It was a WikiHow on falling asleep to audio books. It recommends checking out audio books from your library and playing them on very low-volume while laying in bed. Apparently, nonfiction and classic literature are great for lulling one to sleep! I'm not sure how I feel about this. Classic literature as a sleep aid? Hmmmmmm....