GIMP An EXCELENT FREE alternative to Adobe Photoshop! GIMP is the GNU Image Manipulation Program. It is a freely distributed piece of software for such tasks as photo retouching, image composition and image authoring.
GIMPshop GIMPshop is a modification of the free/open source GNU Image Manipulation Program (GIMP), intended to replicate the feel of Adobe Photoshop. Its primary purpose is to make users of Photoshop feel comfortable using GIMP.
Paint.NET This is an AWESOME light program for editing photos! The program is small in size and works on older computers with no problems!