“Silk” is a smooth, free icon set, containing over 700 16-by-16 pixel icons in strokably-soft PNG format. Containing a large variety of icons, you're sure to find something that tickles your fancy.
“Silk” is licensed under a Creative Commons Attribution 2.5 License. This means you may use it for any purpose, and make any changes you like. All I ask is that you include a link back to this page in your credits (although a giant link on every page of your website really isn't needed, contact me to discuss specifics).