It’s powered with prototype.js and script.aculo.us: nice!
If you use the script.aculo.us slider control to capture input values, it’s really just a matter of converting those values into something useful and modifying styles.
<script src="http://www.agilepartners.com/scripts/prototype.js" type="text/javascript" language="javascript"></script>
A simple demo. (a Cut&Paste from the source site ;) )
Created by Agile Partners.com. I suggest to read the howto: it’s simple and clear. And demonstrate the power of script.aculo.us and prototype.js.
Source, Downloadblog.