TwistedBrush Pro Studio - A powerful and unique natural media painting program.
Pigment by ShapeFactory - A unique way to explore color using lighting and pigment
Corel Painter - Corel Painter is media painting software.
ColorMe - Visualize The CSS Color Function
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.
ibis Paint X - Drawn with + ibisPaint