Is there a resource (e.g. a website) to identify a lego set based on a selection of parts?

Question

Is there a resource (e.g. a website) to identify a Lego set based on a selection of parts?

For example, I have inherited a big box of Legos including several castle-type pieces. Is there a way to figure out what sets those may gave come from?

Answer 1

BrickLink itself has such a feature - had I known, I would not have written my own a year ago.

Brickit is a new entry in this arena; I haven't used it myself.