Colors - House of van Schneider
Popular shots on Dribbble
Colourcode - Color palette
colourco.de is an online designer tool, which allows you to easily and intuitively combine colours.
TinEye Labs - Multicolr Search Lab
TinEye is a reverse image search engine. Search by image: Give it an image and it will tell you where the image appears on the web.
Coblis — Color Blindness Simulator – Colblindor
Color wheel, a color palette generator | Adobe Color