Sites de Banco de Imagens e Ícones gratuitos

Começando por dois dos meus favoritos:

https://visualhunt.com/

www.iconfinder.com

https://photodune.net

http://littlevisuals.co

http://stockvault.net

http://www.uhdwallpapers.org

http://www.gratisography.com

https://unsplash.com

https://stocksnap.io

https://seeklogo.com

http://everydayicons.jp

https://pixelbuddha.net

http://graphicburger.com

http://epicantus.tumblr.com

http://getrefe.tumblr.com