When I was around 11 or 12, my family was on a kick where they got together and prayed the rosary. This was uncles/aunts, etc. Occassionaly my family members would get really excited that the cross on the wall was "flashing." I was excited too when I saw that there were flashes of light to either side of the cross, each in the shape of the crucifix itself. My aunts and uncles would happily say over and over, "there it is," "there it is again!". They stopped getting excited about it one day when I pointed out that the wall socket, too, was "flashing".
I thought I'd share this story with ya'll cause it does such a good job of showing how ignorance about real phenomena can lead one to believe in a higher power. The "flashing" was because people were staring at the cross long enough for it to be imprinted, so when they looked to the side, the after image of the cross was still there.