A big part of male friendship is making fun of each other without any tact whatsoever. In order to laugh at ourselves, we need our buddies to laugh at us first. Still, in every bromance, one guy sometimes goes too far -- and crossing that line can walk any friendship right off the plank.

For example, take the tale of Scottish guys John Grierson, 27, and Michael Mulholland, 32. A year ago they were drinking and joking around at an apartment, as pals do, when the latter reportedly mocked Grierson's disability. The BBC reports, Mulholland "called [Grierson] a 'peg-legged pirate' and tried to pull his prosthetic leg off."

At a trial earlier this week, Grierson told the jury that he then took out a couple kitchen knives to "scare" his insensitive friend, but things escalated quickly and Grierson non-fatally stabbed Mulholland's throat, according to the BBC. Mulholland testified that it felt like a punch, but he soon realized he was bleeding.

The jury deliberated for two hours before acquitting Grierson of the attempted murder charge, finding that intent wasn't proven. No word on whether Grierson and Mulholland ever forgave each other for the incident, though that would arguably be good form.