Open Peeps - A hand-drawn illustration library.
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.
skribbl - Word guessing based on drawing.
Autodesk SketchBook - SketchBook drawing and painting software provides designers, architects, and concept artists the tools to sketch ideas quickly and create beautiful illustrations.
Fontself Maker for Photoshop - Turn any lettering into color & vector fonts
Clip Studio Paint - The artist's software for drawing and painting.