I realize that pretty much anyone who's anyone has a copy of Photoshop they bring out to do any heavy image editing. I also realize that no one would ever have an less-than-legal copy of the $650 program. At least no one I know. And certainly not me.
But if you're tired of deciding between your image editing program and, say, the mortgage payment, you should check out GIMP. For just about everything, it is a drop-in replacement for Photoshop. It is also open-source and free. The latest 2.4 version is nicely integrated into the OS (previous versions looked a little odd). There's even a Windows installer (sorry, you Mac people will have to figure it out on your own).
There might be a bit of a learning curve, but there's good documentation. Just about anything you can do in Photoshop, you can do in GIMP.