I want to give an element a border-top with a tab at the right corner like this:

Since this will be a repeated element within an Adobe Business Catalyst template, I want it to be pure CSS or at least CSS and javascript, without the use of any images. Is there any way this can be done?
Since it’s just a decorative element, it doesn’t have to be cross-browser.
Have a look at this:
http://jsfiddle.net/8hB7E/
HTML:
CSS:
It utilises the :after pseudo-element (which I find to be really useful!)
For more info see here:
http://coding.smashingmagazine.com/2011/07/13/learning-to-use-the-before-and-after-pseudo-elements-in-css/
Unfortunately this won’t work in IE7 or 6 – it’s not core to the functionality of the website though, so I’d say it’s ok as is.