I've resisted posting my effort at a moving eyes animation, but my resolve has crumbled[1].
In an attempt to make this comment slightly less spammy, I think that it's easier to create this effect in a web page if the code makes good use of radial gradients. Both SVG and the 2D canvas API use a 'two circles' approach to defining the gradient (interactive demo here[2]); the CSS approach, however, seems a lot less intuitive to me[3] - can I assume there were good reasons why the CSS committee chose to do it this way?
