The shots in the this week Auto Express, which were taken by our German sister magazine Auto Bild, confirm how modern equipment can become dangerous missiles if their mountings are not secured properly.
The tests, carried out at the internationally respected DEKRA crash facilities in Klettwitz, Germany, reveal how the impact of a rear-end collision can tear a DVD player from the driver's headrest, jolt mobile phones in their cradles and send sat-nav units crashing on to drivers' feet.
Our main pictures show how a DVD player hits a baby dummy sitting in the rear seat, which would cause potentially critical head injuries in real life. And alarmingly, this simulated accident happened at only 18mph.
"The possible consequences of an accident like this are serious injuries," said a spokesman from DEKRA. The DVD player set-up looked secure - a black nylon bag with enough space for a player with a retractable display, a rechargeable battery and some DVDs. To use the device, the bag is attached to the headrest.
In the crash test, the Velcro fastening was torn from the bag, and the player hit the dummy's head. This happened even though the bag was correctly fitted, and the strap had been checked by technicians before the test. Cheap fastenings for mobile phones also fared badly. Where a car was fitted with a sucker and cradle for the mobile, the cup remained firmly fixed to the window - but the phone itself came loose and flew through the vehicle.
"It could easily have hurt a passenger in the back seat in a real crash," continued the spokesman.
Portable satellite navigation systems also came under the safety testers' spotlight. They found that, while sucker cup holders for sat-navs passed the crash test, another variant - which fixes to the air vent - failed completely. The mounting flapped down on the vent and broke in two, smashing the cradle and sat-nav on to the feet of the dummy in the driver's seat.
What's more, to reinforce the importance of fitting items in accordance with the manufacturers' guidelines, testers attached one sat-nav cradle incorrectly - and the consequences were disastrous. During the impact, the unit flew dangerously through the car, again posing a risk to occupants in the rear.