Goodreads - See what your friends are reading.
LibraryThing - A home for your books.
Readernaut - We are a small community of readers, sharing our adventures and supporting each other as we persue a life of learning.
Libib.com - Our library management app caters exclusively to home and private libraries.
aNobii - aNobii is a social network for listing books, sharing insights, and meeting people.
BookBuddy - Kimico is a software development company focused on bringing you Essential iPhone and iPad apps designed to keep you organized.