XRAY: look beneath the skin
XRAY is a bookmarklet for Internet Explorer 6+, and Webkit and Mozilla based browsers (including Safari, Firefox, Camino or Mozilla). Use it to see the box model for any element on any web page.
See what's new in this version. Upgrading to future versions should not require changing your bookmark!
If you just want to try it out, simply click the XRAY button above.