Autodesk has made a program free called composite. While its not for the faint of heart and isnt the best for clean up as its a film tool. Its retouching and compositing tools blow photoshop so far out of the water it not funny. It uses 32 bits per channel in floating point color space. Everything is non destructive. Itbhas 2 paint engines. One is vector based. Meaning it uses paths. They are fully editable at anytime as if you are painting in illustrator but with an airbrush. If you are interested in trying it out I am more then willing to help people learn it. It is a full on pro tool so no hand holding in the program but if you are not delivering layered psd to clients this bad boy may be something to consider. Its windows linux and mac. Just google
Autodesk composite 2014
Again steep curve and its designed for motion picture work but if you do photocomp it will put photoshop to shame.
