Elegant Themes present absolutely free Icon Set for your web applications. This Icon Set was produced when the author could not find icon set for it's wordpress themes. So he sat down all day and drew a set of basic web icon to be used here at ElegantThemes. Now that he has a decent collection, so he has decided to release them for free. Hopefully next time someone is looking for some stock icons to use in their commercial project they will have to look no further! These icons are restriction-free. Feel free to use and abuse them, redistribute them, resell them, or anything else you can think of. If you like them, then thank me by linking to this blog post Officially these icons are dual licensed under the GPL and MIT licenses.

The pack includes 74 48×48px PNG icons.

Source: http://www.elegantthemes.com/blog/resources/elegant-themes-icon-pack-for-free