Programs so far:
- Gimp 2.4+
Paint.net
iScribble
Inkscape
http://gimp.org/

IntroductionGimp 2.4 or higher is probably one of the most faithful representations of a GNU Image Manipulator. It has a vast array of mods, and hardware options. What else, it's multi-platform software, so even Mac OSX and Linux can run it. It's more of a do-it-yourself manipulator however, so instead of having a 'radial glow tool', you would have to duplicate the layer, apply a gaussian blur on the upper layer and then decrease the opacity slightly. Some may prefer this, but the more easy-going should stick towards Paint.net.
FeaturesWhat's really useful about Gimp is its path tool, which allows you to form shapes with curves and lines rather than attempting to draw the shape. It makes good use for vectors and professional logo design. Its vast array of selection and colour tools make good use for both image retouching and image authoring.
Here is its supported file formats available for use. The brighter formats represent reccomended formats:

InterfaceThe interface is probably the most noticeable difference between Photoshop and Paint.net. The application does not run in just one window but many at once. For example one window would be for the Basic tools such as the paintbrush and magic wand tool [see image below].

The second window would be the image you are working on, the dialogues above it would include the filter and colour tools, and the last window would be for use with the layers and history. Although this does take some getting used to, the overall result of your work will pay off.
Overview- Very Customizeable
Open source and multiplatformal
Hard to get used to
Path tools :)
Very Professional
Works with many formats
http://www.getpaint.net/index.html

Paint.net remains the easiest to use and feels almost exactly the same as photoshop. It comes with a wide range of filters and is very Microsoft-Friendly. It's a lot more automated but not as reccomended for drawing. It is well known to get the job done quick.
Paint.net is, as mentioned earlier, easier to use and has much more preset effects available for use. Some special effects include rendering capabilities that are far more expansive compared to its rival Gimp (for example, some tools add perspective). It's auto update feature is very handy and is what every GNU software needs. With this in mind, it remains the most stable image manipulator on the web.
The interface looks very nice and removes the clutter of multiple windows by adding a transparency to them. Paint.net focuses more on providing a user-friendly feel for its users. The image you are working on remains in the center of your window and is comfortable to work with. This does however affect the amount of RAM required to run it, anything under 512mb of RAM will have a slight difficulty with processing requests.
http://www.getpaint.net/screenshots/pdn310_car.jpg
- Easy to use
Windows only
Looks terrific
Takes up more memory
Less clutter
http://iscribble.net

iScribble is meant to be a hobby oriented drawing Application. It's one of the few capable drawing programs executable in a browser's window. It's also one of the only drawing applications that allow you to COLLABORATE drawings with other users all over the world and publish them in a gallery for others to see. It doesn't come with much tools and *undo features* but once again, it's more hobby oriented and isn't meant to draw professional digital art.
The only disadvantages it has is the limitation towards new users. To prevent spam and worthless drawings in the gallery. Only priviledged users that comply to the certain requirements will be allowed to use blur, circle tools, publish works, and comment on them.
See the FAQ for more details: http://www.iscribble.net/faq.html
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http://www.inkscape.org/index.php?lang=en

IntroductionInkscape is a free, and very useful multi-platform program that creates vector graphics and images. It is comparable to high dollar programs such as Adobe Illustrator. There is a slight learning curve to the program with all of it's tools and options, but with the help of some tutorials and some practice, professional work can be made with Inkscape.
FeaturesWith it's useful vector tools you can shrink / increase, push vector's over with out any risk of anti-aliasing. You can also use patterns to simulate gradients, and even convert a normal image into a vector. Think of it as a much more advanced and professional alternative to Flash's drawing tools. You can also generate paths rather than drawing each manually, it works really well for hair strands and eyelashes.
InterfaceThe design and mobility of the interface is limited but it totally eliminates any possible clutter. It is fitted into only one panel and the right area of the window is for the currently selected tool's options (most of the time). It does take some getting used to due to the multiplicity of commands that can be found. But with the proper training and use it can eliminate any difficulty in using it.
Overview- Very Professional
Multi-Platform
Wide variety of tools
Vectors are great to work with
Hard to get used to
Only 33Mb
Opens in seconds
ipwnall: Fixed a few broken links.











