Microsoft Paint - Paint (formerly Paintbrush) is a simple, ultra-basic graphics painting program that is included...
Online Image Editor - Online editor for images and animated gifs with multiple effects and tools
MyPaint - MyPaint is a fast, distraction-free, and easy painting tool for digital artists.
Pixelitor - Pixelitor is a cross-platform raster graphics editor written in Java.
Krita - Krita is a professional FREE and open source painting program. It is made by artists that want to seaffordable art tools for everyone. Concept art. texture and matte painters, illustrations and comics.
RealWorld Photos - RealWorld Photos is an free portable photo editor for Windows.