• Free Icons - Axialis

From author's site:

You need icons? Here is a library of icons that you can freely use in your projects. All the icons are licensed under the Creative Commons Attribution License. It means that you can use them in any project or website, commercially or not.

The only restrictions are: (a) you must keep the credits of the authors: "Axialis Team", even if you modify them; (b) link to us if you use them on your website (see at the bottom of this page).