SixRevisions has collected a list of 10 Free & Open-source alternatives to Adobe PhotoShop on their blog.

Adobe Photoshop is a given in any designer’s wish list, and it comes with a host of features that allow for excellent and professional photo editing. The biggest obstacle to any designer who wants Photoshop is the price, which can be prohibitive. Fortunately there are a number of open source (and completely free) programs out there that do much of what Photoshop can, and sometimes more.

Of course, they open with Gimp, but they also cover some other less common ones like Krita, ChocoFlop, and Pixen.

10 Excellent Open Source and Free Alternatives to Photoshop.