This comes from a Battletech game I ran a while back:
I run Classic Battletech games, but I incorporate a lot of RPG elements into it. For example, I use the Maximum Tech dueling rules (which resembles the combat systems from several more traditional RPGs with its incidental, simple, and full actions), and I also use Pilot/Crew special abilities, which are not unlike Talents in Dark Heresy or Feats in Dungeons and Dragons 3.5. One notable special ability is called "Edge", and is the focus of my little story.
Edge works much like Fate Points in Dark Heresy in that you can spend one to re-roll something. Unlike fate points, however, you can also use Edge to force a re-roll of something that's being done to you, which is just as well; in a previous campaign, player characters were dying at an alarming rate, and several of the deaths were due to head shots on the Battlemech the affected pilot was in by some sort of heavy weapon, like AC20s or Gauss Rifles. A 'mech could be pristine and yet be suddenly put out of action due to the entire head (and the pilot in it) being vaporized by a lucky shot. In response, I started awarding one-use Edge points for certain scenarios and subsequently, player-character survival dramatically increased.
With all that in mind, we come to my little anecdote.
Situation: the players (5) form a Clan Wolf-in-Exile assault omni-mech star and are facing off against a Word of Blake assault Level 2 (six assault-class battlemechs). One of the Blakist 'mechs has just fired a Gauss Rifle. Rolling for hit location, I roll boxcars (12) on 2d6, a dreaded head hit.
GM (me), to target player: "If you have any Edge left, now's a good time to use it."
The target player subsequently spends the last point of Edge he had, and as I go to re-roll the hit location, a fellow player says, "You should be fine. There's just no way he'll roll another head shot."
I roll, and I get . . . boxcars (12). Again.
At that point, we all started laughing.
-Kirov

