VisualSearch.js enhances ordinary search boxes with the ability to autocomplete faceted search queries. Specify the facets for completion, along with the completable values for any facet. You can retrieve the search query as a structured object, so you don’t have to parse the query string yourself.

You can also check out the live example of a search on DocumentCloud.org that uses facets. VisualSearch.js is an open-source component of DocumentCloud, and it is hosted on GitHub.

Requirements: jQuery Framework
Demo: http://documentcloud.github.com/visualsearch/
License: License Free