A Finnish beverage. It is created by mixing koskenkorva with salmiakki. The resulting product is a black liquid, darker than your deepest fears, more potent than a sledgehammer to your face. Some have even dubbed it "Flakpanzer Fuel". As far as I know, only the Finns actually drink this stuff.
My advice would be to drink small quantities of this stuff at a time, as drinking larger quantities becomes more of a chore, really (well, at least for me). If, however, you are really pissed (or lacking complete mental control), and decide to drink the whole bottle, be sure to have your favourite hangover remedies standing by when you wake up. You're gonna need them.