In my photo class that I'm taking, one of my peers was trying to "Solarize" (I've heard this technique is actually called something else, like Sabatiar or something) a print (cheap VC paper) during development. He tried using overhead lights but to no avail. Finally (after a call from a friend) he got the idea to use his cell phone...and it worked! Parts of the image were solarized, making the photograph really interesting. Next time I'm in the darkroom I might have to try waving my cell phone around.