Retrievr is an experimental service which lets you search and explore in a selection of Flickr images by drawing a rough sketch.
They are still in an experimental phase, but the idea itself is really cool. You may also use different colours in your sketch to get better results
You know what, I had a similar idea long time ago, but it was for music files. Sometimes you know some music but you don't know the actual song's names, so why there is no search engine where you can hum or sing a song for it to find it for you.
Tags: Search, Photos, Gr33n Data