Like.com is a new search engine that allows users to search similiar images based on visual signatures. The Like.com engine takes both text and images as input and compares a ?visual signature? for the image to yield similiar looking image results. The visual signature is simply a mathematical representation of the image using 10,000 variables. If enough variables are identical, Like.com decides the images are similar.
In future, one would be able to upload an image to Like.com to see similar results.

Via Techcrunch