Rusting Aluminium
Look what you can do in an hour with a bit of mercury paste.

According to the following article:

Unless you are a representative of a national meteorological bureau licensed to carry a barometer (and odds are you’re not), bringing mercury onboard an airplane is strictly forbidden. Why? If it got loose, it could rust the plane to pieces before it had a chance to land. You see, airplanes are made of aluminum, and aluminum is highly unstable.

I had no idea that you could make such a mess of aluminium in such a short space of time.

I also never thought that a weatherman with a death wish could pose a greater threat to aviation safety than your average shoe bomber.