Paintbrush - By using Paintbrush, you can create images of all types with a simple format and a few templates.
miniPaint - Online graphics editing tool use HTML5 technologies like Canvas, Offline support, Drag and Drop.
SpeedyPainter - "SpeedyPainter" is a simple and lightweight painting software.
RealWorld Paint - RealWorld Paint is an free portable image/photo/animation editor.
KolourPaint - KolourPaint is a free, easy-to-use paint program for KDE (a desktop environment for UNIX).
JugiPaint - JugiPaint is a painting software with diverse tools for various types of illustration work.