Photoshop Alternative GIMP Free Download By: David Rader II on October 28, 2007 @ 12:12 PM
The name: GIMP The site:http://gimp.org/
What it does: Allows you to make intricate graphics and save in many file formats, including Adobe Photoshop (.psd). Is it free: Absolutely. Free download.
What operating systems does it run on currently? Check here to be up to date.
Here's a graphic I did to provide you with a simple example of what can be done with this program.
If you're interested in learning about a free vector based graphics program also, I recommend Inkscape. Vector based graphics are highly scalable, so they don't loose resolution and become grainy.