If you want to know what's in the world's libraries, including probably your own, and your mom's:<p><a href="http://www.worldcat.org/" rel="nofollow">http://www.worldcat.org/</a><p>At the top is a search for:<p><pre><code>  [Everything] [Books] [CDs] [DVDs] [Articles]
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Under that is a link to "Put WorldCat on your mobile phone."<p>There's a collection of tools, including an API.<p>You can use a bookmarklet to go from "product on page you're on now" to "details of product in the library."<p><a href="http://www.oclc.org/news/announcements/announcement333.htm" rel="nofollow">http://www.oclc.org/news/announcements/announcement333.htm</a>