Quite possibly the coolest ship in the Navy.
Fully Auto Glock Pistol Action
A German company sells a drop in full-auto selector switch that replaces the back plate on your slide. It costs $280. (Be advised from the get-go that in all US states full auto Glock is, of course, illegal as all get-out! Unless you get the special permit to own this from ATF you are looking at hard time plus losing your right to own firearms FOR LIFE.). Guy #1 just holds the trigger back, does a mag dump and winds up shooting at invisible birds and also scaring the crap out of himself. Guy #2, at a very lenient indoor range, is smart enough to only shoot short bursts and has control of the gun.