IconLover - Icon editor for Windows.
Tiled Map Editor - Tiled is a general purpose tile map editor.
VistaCreate - The VistaCreate is a free and global digital platform which is known for sharing, searching, finding, and creating great art.
Tilesetter - The tileset designing software.
Lospec Pixel Editor - Free online pixel art program. It's easy to use, intuitive and unobtrusive.
Art Set 4 - Art Set 4 is the extravagant and intelligent Painting and drawing application that facilitates you to create drawings or painting with the help of a variety of different features and functionalities.