use the website i posted in the op to see css3 goodiness in action.

In a theme I'm working on, I've replaced the background graphics for the forum table headers with css3 gradients. Most (if not all) modern browsers support them - even mobile browsers), and if they don't, a solid block of colour will be shown instead, so it's backwards compatible. the code? simple!

from www,css3please.com where the gradient is red at the top, and white at the bottom:

background-color: #ff0000;
  background-image: -moz-linear-gradient(top, #ff0000, #ffffff); /* FF3.6 */
  background-image: -webkit-gradient(linear,left top,left bottom,color-stop(0, #ff0000),color-stop(1, #ffffff)); /* Saf4+, Chrome */
  background-image: -webkit-linear-gradient(#ff0000, #ffffff); /* Chrome 10+, Saf6 */
  background-image: linear-gradient(top, #ff0000, #ffffff);
            filter: progid:DXImageTransform.Microsoft.gradient(startColorStr='#ff0000', EndColorStr='#ffffff'); /* IE6IE9 */

if you want to be really fancy, you could use rgba to define an alpha of the gradient!

using css3 gradients is a lot faster, and doesn't need to pull the images!