Usability.gov - Resource for user experience (UX) best practices & guides
UX Flow Wireframe Prototyping System - Create beautiful user flows prototypes for your next project
Digital Psychology - Elevate your product using psychological techniques
Freddy Feedback - Freddy Feedback is a tool to get feedback from your visitors and customers on anything that you communicate to them on your website.
UX Check - Easy heuristic evaluations on your website (chrome ext.)
Userflows - Automatically generate user journeys