XdoX - Start challenges, log your progress and also get a unique profile page!
Goodreads - See what your friends are reading.
The Bored Hoard - Sieve the web for cool websites you probably never knew existed. Supporting the smaller independent sites that Google ignores. All revealed in a weekly box delivered online every Friday.
LibraryThing - A home for your books.
Confetti - Confetti is the all-in-one tool for all your conferences, festivals, workshops and social events.
GoodBooks.io - Largest curated collection of 8,500+ book recommendations.