Kaligi - Co-op puzzle game that tests loyalty and communication skill
GoodBooks.io - Largest curated collection of 8,500+ book recommendations.
Trivia for Google Chat - Team-building w/ fun quizzes, games right inside Google Chat
BookAuthority - BookAuthority collects the most recommended books on business, technology and science - as featured on CNN, Inc and Forbes
TeamBuddy - Team building for remote companies
Goodreads - See what your friends are reading.