TheStoryGraph

GoodReads was bought by Amazon in 2013. Amazon has a tendency to recommend items that are best for their bottom-line, not the items that you would appreciate most. TheStoryGraph is a great alternative and uses machine learning algorithms to recommend you interesting books. Note that you can buy a subscription (so you are the client!). I first heard about them on the "CoRecursive" podcast and am looking forward to using more of their services!