Crowdsourcing has enabled the creation of online platforms like aNobii that leverage the wisdom of crowds. ANobii is a social networking site for book lovers that allows users to catalog books, write reviews, create lists, and connect with other readers. It has over 400,000 members and almost 17 million books catalogued through user contributions. While aNobii faces sustainability challenges as a free social platform relying on partnerships, its crowdsourced model has made it a leader for online reading communities in Italy through the collaborative efforts of its global volunteer base.