A search interface to a local copy of the MDN CSS Reference
Try it out here: http://morrow.github.com/css-reference
Inspired from: This Hacker News article and this web-page.
If you want to generate a local version, you need ruby capable of running the scripts in scripts/ (call via scrape.sh)
To run, serve the files on a local server, and either set up routing to /#/attribute, or just redirect to the client-side javascript router called 404.html
It won't work dynamically with a local file:/// url, as local AJAX requets aren't allowed by Access-Control-Allow-Origin, but there is an index of the files under html/index.html.