Aseprite - Aseprite is an art program dedicated to the creation of pixel art.
Tilt Brush - Paint in spaces around you with Virtual Reality
Pixel Art Studio - A purpose-built drawing tool for pixel artists
JS Paint - JSPaint is a web-based Microsoft Paint remake
Piskel - Piskel is a website where designers online create sprites or pixel art.
PaintCube - Web-based 3D painting software