Long ago, you couldn't see what the library had by looking at the catalog on the Web. You had to go to the library and look at the materials. And what happened when you went to look for something at the library was that you saw an intriguing title on your way to what you were looking for, and then you let yourself get a little bit sidetracked, and you looked over some other books nearby, and then you thought of something else you heard about or thought about or read about or saw on television or just realized you were interested in, and you went off to look that up, and maybe you passed the New Book display on the way and found something by your favorite author that you didn't even know was out yet.
This was known as browsing. Well, it IS known as browsing, but it doesn't happen as much any more, because the availability of the online catalog means that you can look up exactly what you're thinking of at the time, put it on hold, go pick it up ... and never experience the serendipity that often came - comes - with browsing. The word "browsing" is probably still used more than the word "dowsing" ... but perhaps not by much.
But don't despair. Allen County Public Library has recently launched a Web feature that casts browsing in a whole new light. Sean Robinson, head of IT Services at ACPL, created a mashup of book covers and information for the books cataloged at ACPL yesterday.
This is the new browsing: http://blog.acpl.lib.in.us/amzamash/book_wall.php
When you click on the cover of a book, you get information about it - on a little graphic of an old-fashioned library catalog card (the idea for which Sean got from John Blyberg, of http://www.blyberg.net/).
Edit: I just wanted to point out there is a weakness in my phrasing that makes it unclear that the bookwall is updated automatically - so that every day that items are cataloged, the bookwall changes to reflect the most recent materials.