LibraryThing is an online service to help people catalog their books easily. You can access your catalog from anywhere—even on your mobile phone. Because everyone catalogs together, LibraryThing also connects people with the same books, comes up with suggestions for what to read next, and so forth. It requires no software and you can catalog up to 200 books for free. Anything more than 200 books will cost $10.00 a year or $25.00 a lifetime. For more information and to get started cataloging visit LibraryThing.