GIMP - GIMP is a multiplatform photo manipulation tool.
RealWorld Photos - RealWorld Photos is an free portable photo editor for Windows.
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
Online Image Editor - Online editor for images and animated gifs with multiple effects and tools
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.
SoftColor PhotoEQ - SoftColor PhotoEQ makes color correction, image editing and color management tasks simpler.