free photo editor

Hi, Does anyone know of a decent FREE online photo editor please ? I have been using 'Photo Pos Pro' for some while but the newest version is nowhere near as good as the original and certain tasks have become extremely difficult. Thanks !

I recently came across this article about some of the top free photo editors out there. I agree with maybe 4 out of these 5 (I'm not a huge fan of Photoscape). What's your favorite one to use? I'm a pretty big fan of GIMP myself.