I made a small library that lets you easily use a throbber without images.
It uses CSS3 but falls back onto JavaScript if the browser doesn't support it.
// First argument is a reference to a container element in which you
// wish to add a throbber to.
// Second argument is the duration in which you want the throbber to
// complete one full circle.
var throbber = throbbage(document.getElementById("container"), 1000);
// Start the throbber.
throbber.play();
// Pause the throbber.
throbber.pause();