Really Good UX - A library of screenshots for UX inspiration
Design Principles - An open source repository of design principles and methods
Usability.gov - Resource for user experience (UX) best practices & guides
Facebook Design Resources - A collection of free resources made by designers at Facebook
UX Check - Easy heuristic evaluations on your website (chrome ext.)
Facebook - Connect with friends, family and other people you know. Share photos and videos, send messages and get updates.