When I’m working on a design using CSS3 features, I often worry about how things are looking on older browsers. Sure there’s VMware Fusion or Parallels, but that’s uber clunky for just a quick view of how things are shaping up for older browsers.
deCSS3 is a bookmarklet that lets you get a view of what your site will look like on older browsers that don’t support CSS3.
It doesn’t remove all CSS3 right now, but I’m sure that Dave would gladly accept a pull request. Oh, and BTW, they are looking for collaborators with some regex-fu.
Currently supports: Chrome, Safari