PicEdit

PicEdit is an image-editing tool that you can use to retouch your favorite photographs from a simple, accessible interface that still manages to include tons of interesting features.

You can access many of these options with just one click, including 'sliders' that control brilliance, contrast, saturation, and hue, and effects to pixelate, blur, or add noise to the image. You can also invert colors or change an image to black and white in just a second.

Other tools are located on the top tool bar, allowing you to draw arrows, rectangles, circles, and text boxes right onto the image. Of course, you can also rotate the image however you wish, and even add watermarks.

PicEdit is an interesting tool for several reasons. First of all, it's much more lightweight than any other similar program. Secondly, it has included just the right tools. And finally, it has a simple, accessible interface.