Grimthing has an article comparing GIMP, a free open source image editor program to the famous Adobe Photoshop. And the winner is….
“The winner for commercial printing – Photoshop. The winner for home use – The Gimp. Bet you saw that coming, didn’t you. The truth is, they’re both winners when they’re used in the proper context. The Gimp just doesn’t have support in the areas that are necessary to make it useful in a commercial application. However, you cannot justify the price of Photoshop for personal use when the Gimp will do everything it can do outside of commercial printing. I know I’ve beat the horse to death, but unless you want to pirate software, there is no reason to use Photoshop if you’re not producing a print publication – use the Gimp.”