Ever been in the middle of a collection quest, clearing out some mobs so you can interact with the garbage bin your quest giver eagerly asks for (that is sitting right next to him) and some jerk comes along, out of nowhere, and steals it? Not only does this leave you to fight your mobs alone, but now you have to wait for that item to respawn.
Have you ever been in an instanced PvP match and one player decides to badmouth the rest of his team and completely ignore the objectives of the map, sometimes even resorting to helping the other team? Ever been in a raid and some noob warlock joins your PUG group and pulls the boss, gets the raid wiped, laughs, and then leaves?
Yeah, me too.
In fact, it's safe to assume that an endless amount people who play online games have been in these situations. It's all too common knowledge that if there is a space that allows for interaction amongst people that use an alias, the worst in many of those people tends to come out. That isn't the case for everyone. There are some quite amazing people that you can befriend through online gaming. It just sucks when you do happen to come across a jerk that tries to rain on your parade and there isn't really anything you can do about it besides send in a ticket to a GM that says something along the lines of, "Herp hurt my feelings and I need you to put him in timeout for me plox."
I mean, I guess you could bad mouth them back, but that'll potentially get you suspended and, if you're a semi-decent person, it won't really make you feel better about yourself. What's the point? This person probably gets a jolly out of the fact that he or she has upset you. So by arguing, or name calling, you are basically saying that they got to you. Successful troll is successful. You don't want that, do you? Heck no! There’s an e-peen at stake here, people!
Perhaps you could roll a toon on the opposite faction, find them, then camp their body till they log off, but that is a lot of work just to get revenge. I mean, I will admit that I may have done this in the past, but I wouldn't recommend it for everyone. It was a waste of time and this doesn't really create a solution for people who tend to be more casual, but are getting harassed by members of their own faction. And not only that, but even sandbox games like Ultima Online have safe zones that these jerks can just sit in and laugh at you all day.
You could put them on ignore, but that also seems like a lot of work. I don't want to have to type out all those letters when I'd rather just virtually slap them in the face with Mjölnir. Not to mention, then you'd feel left out of the loop when everyone else around you is responding to this jerk and you have no idea what he is saying. Curiosity takes its toll and you end up unblocking them. That, or they end up logging onto different toons to harass you some more, because most games haven't come up with reasonable account-wide ignore features yet (hint-hint).
Or what about just being able to kill these people on the same faction? I don't know about you, but I certainly would take that. I guess the argument here would be that there should be no factions then, but I'm not talking THAT extreme and I'm not talking about dueling either. Walk with me for a moment while I paint a pretty picture for you:
Okay so now that we have that out of the way, what would this button do exactly? Well, I'm not by any means a designer but if I had to guess... I would say that it would probably have to have a large cooldown, such as 24 hours. That way you use it wisely (maybe) and can't grief people over and over. It would only be useable on your faction, not the opposite (you can attack them as is). It would likely have to do a significant amount of damage, if not one shot them (Why not? They are jerks). It would be useable anywhere, but you'd gain no rewards or stats from using it (such as in BGs). And if you have strikes against your account for being a jerk, you don't get this button until you’ve paid your dues in death.
So now let's pretend that you're skipping through the woods of Sholazar Basin on your hunter, searching for the rare and elusive Loque'Nahak. You search the usual spots that you looked up on various websites and, right as you're dipping a double stuffed Oreo into your milk, you spot him! Naturally, everything in real life stops, your Oreo falls into your milk, and you make a mad dash to land and tame this magnificent beast. You beat him down some and are in the process of taming him when some jerk-off Failadin drops down, finishes off the beast, then laughs. He calls you a noob, asks "umad", then flies away.
I bet you wish you had that one shot button now... unless you're the Failadin... you jerk.