I am excited beyond words about my new web find. My nerdiness is exhibited most clearly by my shaking hands as I type. No joke, I think this is COOL.
Jon Udell's LibraryLookup Bookmarklet
Long story short, you can make a bookmarklet for your local library and when you are shopping on amazon or barnes and noble or other bookstores that use ISBNs (I'd venture a guess that most do), you click your new bookmarklet and up pops your library catalog and the book you were looking at. How much easier does it get to add new books to your library wishlist or request a copy to a location nearest you?
If you can't figure out his website or how to use your bookmarklets, let me know and I'll try to help.
You have NO idea how often I am going to use this.