Jon Udell’s bookmarklet
A brilliant piece of programming — and an illustration of how innovation happens so quickly on the Net. After you’ve “installed” your bookmarklet in a browser, you can look up books at your local library (provided its catalogue system is run on some industry standard software). Let’s say you’re on a book-related site (Amazon, BN), and a book’s info page is your current page. (Specifically: its URL contains an ISBN. Choose a hardcover edition for best results.) You can click your bookmarklet to check if the book is available in your local library. The bookmarklet will invoke your library’s lookup service, feed it the ISBN, and pop up a new window with the result. This is what Web services are all about.