Well, my personal favorites (also on my blog and wiki)
del.icio.us. share bookmarks and save/find your favorite websites online
Worth1000: www.worth1000.com (amazing PhotoShop photographs. Try Gallery, then browse by category or alphabetically)
http://www.teachertube.com/ A site dedicated to educational video content
A Place Between Us: http://a.placebetween.us/ - need to meet someone half-way? this will do the trick without trying to guestimate who will have to do more driving.