i went there this weekend with my cousin and some friends. this thing is true. it is at an on-ramp to the highway near madison. we had a convoy of 4 cars(suziki sidekick, ford explorer, dodge neon, and prelude). the on-ramp was going down hill. we all stopped our cars at the same time and immediate all the cars began to roll backwards. we all pulled off the road (cept for the lude) and put baby powder on the hood of the lude(it had a cf hood). he went all the way down the onramp near the highway, and began rolling backwards. btw it rolls back pretty fast; around 30mph. he stopped after about 100yards, and sure enough there were handprints. not just one set though, it was like 3 sets of hand prints, but oddly none of them were positioned as if the person was standing in front of the car. the onramp is about 200yards....the "gravity" will pull you all the way there to the gas station; which is at the top of the hill. you guys should go check it out if you go through there. the exact location i dont know though except you take battleground rd from summit ave. we forgot to bring a camera but we might go again this weekend. scarey stuff.