GIMP - GIMP is a multiplatform photo manipulation tool.
FotoFlexer - FotoFlexer is the most powerful online photo editor in existence.
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
piZap - Free online photo editing software.
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.
Fun Photo Box - FunPhotoBox is a free photo editing device where you can make clever pictures from your photographs.