FotoFlexer - FotoFlexer is the most powerful online photo editor in existence.
Aseprite - Aseprite is an art program dedicated to the creation of pixel art.
Photoshop.com - Photoshop.
Grafx2 - GrafX2 is a bitmap paint program inspired by the Amiga programs Deluxe Paint and Brilliance.
Fun Photo Box - FunPhotoBox is a free photo editing device where you can make clever pictures from your photographs.
Piskel - Piskel is a website where designers online create sprites or pixel art.