You also run slower with the rocket launcher, but only when its in your hands.

Damage to body parts is broadly divided into "Head," "Torso," and "Extremities." Shots to the head are generally lethal. Shots to the torso are also lethal, but you generally need to make more of them in order to actually kill someone. Shots to the extremities are only lethal if you really make a lot of them. The trouble with this setup occurs when you blow off a person's leg and they're still standing (literally) because you haven't damaged their health enough to knock them unconscious yet.

People who have seen a lot of the world apparently pick up the ability to shrug off an axe to the face. This is a particular problem in D&D games
The screwjob by a friend & mentor I've known since I was a baby but is really the ultimate enemy
The "I've been working for the bad guys? Oh, suppose I'll change my shirt and shoot at them instead"
The level where you're captured / injured and lose all your weapons. If this is an RPG, you can add the annoying reorganisation of your entire inventory when you get your gear back
Never played a Star Wars shooter then? The stormtrooper blaster rifle is woefully inaccurate from anything other than point blank range

yes but thats from recoil, if round 1 isn't on target then you haven't got a real weapon

Eh, it was still my weapon of choice for when I wanted to spray a lot of ammunition at people.
That reminds me: most games that heavily feature melee combat have some way of balancing melee combat so that it's just as good as gun combat or magical-blasting combat. I have played many games where I found that running up and hitting someone with a stick was faster and easier than trying to shoot them or blow them up.

all games happen in Kazakhstan - worlds number one producer of potassium. ;-)

Bananas have potassium in them, why don't they explode when I shoot them? A banana plantation should go up like a fuel dump

Pure potassium combusts when exposed to the slightest amount of water, or so I'm given to understand. So you could have one of three problems:
1. The potassium in your bananna is bonded with other elements and isn't as volatile.
2. There's not enough water to cause a reaction.
3. You're bluffing, and you've never actually tried to shoot a bananna. You never know until you try, right?

I've shot a banana and they do explode, but only in the messy leave the lid off the blender kind of way.

Oh well. Back to the drawing board, then... I'm sure there must be some kind of substance that's sensitive enough that the heat of friction from a bullet would be enough to set up a reaction... but I'm no chemist.
Back on topic, how about the vehicles of variable stability? There seem to be only two kinds of cars in the world:
Type A: Completely indestructable. Can crash into a solid stone wall at 100+ mph without even scratching the paint.
Type B: Very destructable. If the car sustains enough damage from crashes and/or weapons fire, it will actually explode (like a Pinto full of C4), regardless of what kind of fuel it uses or how it got damaged.

Here's a few (one or two have already been skimmed across):
Repetition of a single-object creation exercise, only to find you aren't quite good enough at the same thing you just made! (Die in a fire, alchemy skills everywhere)
Alias mentioned, but I can expand on it: The mysterious guy who saved your life and turns out to be your long lost ___________ and may or may not die heroically soon after.
In RTS: Mysterious and horrible attrition of your forces via cinematic/load screen from the place a mile away where you were 10 minutes ago. "Dear lord, we need to rebuild an entire base here because that one is too far away! We have to save gas!"
(I admit I still play the RTS anyway)
And finally:
Dear lord, my torch seems to have gone out at a most inopportune time for no explainable reason! *Lights torch, is devoured by nameless horror, only to miraculously escape by some plot contrivance*

I always figured there was a company that produced these exploding barrels called Explo-Bar Inc. and they produced them for one single reason, to place around your home or office or bunker or forest or city.
I've always wanted to place exploding barrels around my house.

If by some means you manage to flip your car, it will catch fire and then it will explode.

The player being the leader. I'd like to play a game where I'm a subordinate for the entire game. Especially an RPG. Being the sidekick to the chosen one and one true hope for our world would be nice for a change. Particularly if you can be the one influencing him through dialogue to be a good guy or bad guy, you could be the hero's conscience or play the role of Iago and basically just enjoy being a manipulative bastard