This free icon set contains more than 700 16×16 pixel icons in .png format. Every web developer appreciates this usefull icon set when designing web application with lot of controls. Those are much nicer than written text as well as pretty semantic. The FAMFAMFAM Silk Icon set is absolutely free for both non-commercial and commercial use.
I’ve created 64 new Silk Companion icons… take a look: http://www.cagintranet.com/archive/download-famfamfam-silk-companion-2-icon-pack/