Classy icons crafted according to Microsoft guidelines. Available in PNG and SVG. Free for a link
Google Fonts - Making the web more beautiful, fast, and open through great typography
Feather Icons - Simply beautiful open source icons
Font Squirrel - Font Squirrel scours the internet in search of FREE, highest-quality, designer-friendly, commercial-use fonts and presents them for easy downloading. We don't have the most, but we do have the best.
IconStore - Free icon packs by first-class designers
Fontspace - Free downloads of 70,000+ legally licensed fonts that are perfect for your design projects. The best place in the universe to search for amazing fonts.
Flat Icons - 20,000 unique, customizable icons with free lifetime updates