need help with photo effect

[the boatman]

I'm trying to make a picture go from color on one side and fade into black and white on the other. Or make the photo go from a normal exposure picture on one side to more of a comic book or illustration feel on the other. any ideas?

 

[mfox]

duplicate the original layer; add the effect to ONE of them, and whatever layer is on top use a Layer mask and a gradient