CSS3

There are a couple of WebKit specific properties that make giving text a gradient background possible:

-webkit-background-clip: text;
-webkit-text-fill-color: transparent;

Those will allow the background of the parent element to become the background of the text inside. I gots to thinkin’, if we made a made a horizontal gradient that faded in a gray-white-gray pattern, then animated it from left to right, we could make the iPhone/iPad’s “slide to unlock” screen with no images at all!