GIMP 2.4

GIMP is a free *nix platform program which has been carried to Windows and Mac. It can perform lots of actions, from elementary up to complex image manipulations such as smart smoothing or sharpening to eliminate blurred areas in lots of images. This means it can carry out every action that other bitmap image editing software can do, and even more.
Plugins and procedures are much faster than those in similar commercial products, that are in addition very expensive, since plugins for commercial software are developed (in most cases) by commercial companies. GIMP plugins and add-ons are, on the contrary, developed within the community that utilizes them. This fact brings a very important added value: somebody has already solved the problem that you are dealing with.
GIMP is highly configurable, both its tools and the user interface, and as tool and layer palettes are independent from the main edition window, you can use all the screen surface as workspace.
The application also has macro and multi-language support.
This software is under constant development and enhancement and its hardware, disk space and system resources requirements are just ridiculous in comparison to its quality.
GIMP´s only limit is your imagination.