GIMPshop
GIMPshop is a modified version of GIMP that's made to look and feel like Photoshop. GIMPshop has all the same features, but addresses confusion issues for people making the switch from the costly Photoshop program to the free GIMP program. Another advantage to mimicking Photoshop is that tutorials written for Photoshop are applicable to GIMPshop.
GIMPshop is free and open source, so if you are looking to continue working in photo editing with all the advantages of photoshop, but without any cost, give GIMPshop a try. You may not even notice a difference, as the author intends.