PNG ICO ICNS MORE
Desktop apps
Smooth
Sleek XP: Software
chrome, google
Black
128x128
Social media
Aquaticus
google
Silver
60x60
Web social icons
Badge, google
WhiteSmoke
google, Picasa
Computer & hardware
Futurosoft
Blue, google, gmail
Gainsboro
red, google, gmail
UI
Function icons
google, button
48x48
Web 2 icons
512x512
Icons Web 2.0