Icons can enhance your web design and add to the user experience. With all the icon sets out there it is hard to narrow it down to free quality icon sets. I have compiled a list of some quality icon sets that I hope will be useful for you. Feel free to post your favorite sets as well.
This icon set includes many useful icons including social icons like Skype, and Facebook although the twitter icon is outdated.
Here is a great flat icon set, it includes some really good icons directed at web designers
Here is a set of great weather icons.
Here is a great set of clean line icons
This set has some creative icons, and contains 1200+ icons!
A well designed icon set inpired by IOS 7 design.
Beautifully designed rounded icons.
Flat flag icons that are very visually appealing.
Here are some nicely designed icons from Designmodo
Here are some flat social media icons.