Kerbal Space Program

When activated airbrakes hit the ground, they suddenly spring back the whole craft with a lot bigger force than plausible, creating the possibility for a perpetuum mobile. The video was created with ker and chatterer added, but this was tested unmodded too. 32 bit windows version 1.0.5.1028 (from the ksp store), running on windows 10 64 bit. In the output log the craft lost an airbrake to collision, after that the remaining 3 still caused the jump.

Sample video: http://www.warpology.com/k/perpetuum_mobile.mp4
Sample craft: http://www.warpology.com/k/Droptest.craft
An output log: http://www.warpology.com/k/output_log.txt
System: http://www.warpology.com/k/DxDiag.txt