GoodBooks.io - Largest curated collection of 8,500+ book recommendations.
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Readernaut - We are a small community of readers, sharing our adventures and supporting each other as we persue a life of learning.
Read This Twice - Verified book recommendations from people we look up to
LibraryThing - A home for your books.
Bookicious - Find the best new book to read with books collections for makers, founders and entrepreneurs.