Viewdle - Search in Video. Reuters Labs. MyFaceID. Goggles - Use pictures to search the web. There are some things that are hard to put in words, like a painting that you want to find out the artist of.
For searches like that, try Google Goggles -- it lets you search the web using photos that you've taken on your mobile phone. So just open the Goggles app on your phone, snap a photo of that painting, and find search results all about it.