IconLover - Icon editor for Windows.
Aseprite - Aseprite is an art program dedicated to the creation of pixel art.
VistaCreate - The VistaCreate is a free and global digital platform which is known for sharing, searching, finding, and creating great art.
Grafx2 - GrafX2 is a bitmap paint program inspired by the Amiga programs Deluxe Paint and Brilliance.
Lospec Pixel Editor - Free online pixel art program. It's easy to use, intuitive and unobtrusive.
LibreSprite - Free and open source program to create animated sprites.