Today’s invention is a stupid river crossing using stunt driving and hopelessly elaborate technology (but I can’t help feeling there’s a good idea somewhere in there ;).
To get a car across a river:
Lock the coil in the position shown in the top part of the image and drive down it fast enough to loop the loop, stopping carefully before crashing into the door on the mid-stream end (think Italian Job).
Engage reverse gear so that the vehicle stays still and the coil threads its way across to the other side.
Lock the coil in place on the far bank and repeat the looping drive (this time forwards) before exiting through the end hatch.