Now search Images by colors...
http://www.shutterstock.com/labs/spectrum/



Looks great feature to me... check it out

DT has had a Search by color feature for a long time but it is buried in their advanced search features and a bit clunky. You can enter search terms and then apply a primary and secondary color to the search. I wonder how many buyers might use it though on either site.

iStock has had 'search by colour' for years.

Great interface -- even if it's not a new idea. Very beautiful implementation.

Very cool.  Easy to use.

Yes, nice implementation.