I just came across this website – http://www.colorgorize.com/about/

The first version of Colorgorize was published in 2007 as a project at the University of the Arts Bremen, Germany. Back then, Colorgorize was a Firefox add-on that could display similar colored websites to the website currently opened. Colorgorize was changed to a website in 2009 to reach a bigger audience. Today, thousands of websites are already analyzed and can be searched by colors.

Colorgorize is essentially a site where you can get inspiration for web-design colours and palettes. It works by shrinking imags of webapages that can be organized according to your colour preference.