Picnik seems to be the most popular online image editor in this list. The interface of the site is beautiful, responsive and can put many desktop applications to shame. You don’t need to know anything about photo editing to use Picnik. Most noteworthy feature is its integration with other Web2.0 services. You can pull photos directly from most photo sharing sites such as Flickr, Picasa Web Albums, Facebook, Photobucket and pretty much provide any image URL to start editing it. No registration required.
· Fix your photos in just one click
· Use advanced controls to fine-tune your results
· Crop, resize, and rotate in real-time
· Tons of special effects, from artsy to fun
· Astoundingly fast, right in your browser
· Awesome fonts and top-quality type tool
· Basketfuls of shapes from hand-picked designers
· Works on Mac, Windows, and Linux
· No download required, nothing to install
· All this for free!