My current favorite web site!  Diigo is referred to as a social bookmarking site, but its become my own personal online library.

One of the main reasons I love it, is its mobility. In my current job, we have a collection of shared computers at four different work areas. If I find a site I like, it gets bookmarked on Diigo, versus one computer browser where I’m sitting today, and I can access it wherever I happen to be working tomorrow….or even from home this weekend.  By tagging your bookmarks, with time, you establish a filing system of your web sites.  The flexibility is super convenient!