Extracting only the css used in a specific page

I've used Dust-Me Selectors before, which is a Firefox plugin. It's very easy to use and versatile as it maintains a combined list across a number of pages of which CSS values are used.

The downside is that I wasn't able to automate it to spider an entire site, so I ended up using it just on key pages/templates of my site. It is very useful nonetheless.

http://www.sitepoint.com/dustmeselectors/

https://addons.mozilla.org/en-US/firefox/addon/dust-me-selectors/

Contrary to the comment above Dust-Me Selectors 2.2 is compatible with Firefox 3.6 (I've just installed it).

These look promising:

• Unused-CSS.com -- Service that spiders your website and emails you the results
• CSS Usage -- Firebug addon

Hands down the best tool that actually does exactly what you want by only getting the used CSS on the page and allows you to simply copy it to your clipboard is this Chrome extension CSS Used

Pretty Picture Example