Using a four-player 1975 Bally Wizard pinball machine, Canadian Alan Amon has converted it to an atomic alarm clock “an arduino, 8 relays and a gps”. He has posted the entire howto directions on Instructables.
One of the more common problems faced by pinball collectors is where to put the next one. The thought came to me one day – what if I could re-purpose the pinball machine? I could then replace an existing appliance with the pin and my problem would be solved. With that in mind I converted my 1975 Bally Wizard into the most accurate clock in the house. And all I needed was an Arduino, A GPS receiver, an 8 relay board and some assorted odd bits.