RealEye - Online Research Platform with Webcam Eye-Tracking.
UXTesting - Discover how your mobile users feel
Tobii Pro Lab - Eye tracking software for behavior research. Combination with other physiological data while you design, execute, and analyze with heat maps, gaze plots.
Startup Timelines - How the frontpages of famous startups changed over time
SeeSo.io - SeeSo, the real-time eye tracking SDK for the smartphone/tablet/laptop environment. With a users' vision, reach beyond the vision.
Really Good UX - A library of screenshots for UX inspiration