Braille Cube - Rubiks Cube for the blind
Image Colour Transfer - A free-to-use browser-based application that allows an image to be recoloured to match the colours of another image using novel methods.
Linia - You will never look at colors the same way...
Colores - Find color palette ideas via image search
GoCube - The classic puzzle reinvented
Color Palette Generator - Enter the URL of an image and find its color palette