Austrian Pfeifer-Zeliska .600 Nitro Express Magnum

The website is mostly in German and before you start drooling I believe that that caliber limit is .50 in this country.
The weapon weighs just over 13lbs.
It’s a five shot, single action revolver.

Bullet Weight of 900 grains
Muzzle Velocity of 1950 fps
Muzzle Energy of 7591 ft/lbs

The cost is $13,840 Euros.

A handgun of this power is like owning a 200mph sports car. Aside from bragging rights, what good is it out in the real world?

I suppose you could take this beast out on the freeway and hunt eighteen wheelers.