Search by site screenshots

About a month ago I found a good site on Flex, it had a lot of source code and ready-made solutions. Now I can not find it, the second day I sit and the result is zero. Accordingly, the idea was born to make a search engine with standard features, but so that a screenshot was shown next to the found site.

If this has already been implemented, I will be very grateful for the link to such a search engine.