
The spiked helmet was a weird looking helmet that had a handle on it. With a simple turn of the handle, a screw would be driven into the torture victim's forehead. This torture was so bad because it could last for long periods of time while still being extremely painful. All the torturer had to do was twist the crank once an hour and the victim would still be in immense pain. The victim could even survive for a period of time after the screw had broken through their skull. Crazy!
Source and Photo Source:
http://www.occasionalhell.com/infdevice/detail.php?recordID=Spiked%20Torture%20Helmet