Material Palette - Generate and export your Material Design color palette
Opta - Opta is a new kind of Infrastructure-As-Code framework designed for fast moving startups.
Color Hunt - Curated collection of beautiful colors, updated daily
Chain - The Block Chain API for Developers
Color Palette Generator - Enter the URL of an image and find its color palette
Cal.com - Cal.com (formerly Calendso) is the open source Calendly alternative.