Kerbal Space Program

Description:
Driving a small rover into a landing strut from a heavy lander causes an exponential reaction.
At very low velocities, the rover is just flung back, a bit higher and the rover is flung back at a speed sufficient to destroy it and surviving parts travel at ~100 m/s.
The exact speeds seem to vary.

Reproduction:
1) Have any vehicle heavier than a couple of tons landed on struts. This works with both LT1 and LT2 landing struts, i have not tested the others yet. (the vehicle can be held up solely by struts or by struts and other parts)
2) Drive a microrover into a strut. (4 wheels, docking port, OCTO, Battery)

As an aside the wheels and the landing strut do not clip at all, while both the wheels and the struts clip with other parts.

Images:
-a normal "high" velocity impact for comparison

-a low velocity landing strut impact

-a medium velocity landing strut impact

-another medium velocity landing strut impact

-a high velocity landing strut impact