miniPaint - Online graphics editing tool use HTML5 technologies like Canvas, Offline support, Drag and Drop.
Online Image Editor - Online editor for images and animated gifs with multiple effects and tools
RealWorld Paint - RealWorld Paint is an free portable image/photo/animation editor.
Pixelitor - Pixelitor is a cross-platform raster graphics editor written in Java.
JugiPaint - JugiPaint is a painting software with diverse tools for various types of illustration work.
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.