Make sure I look at every single thing before I move out so I don't miss anything.

I shoot only women in any GTA game. Calm down just a joke!

Can't really think of anything, I'm sure i do stuff though.

In Godfather Blackhand edition, I like taking the lit 2x4 and setting people's pants on fire. That was my number 1 execution by a long shot. I also like garotting people for no reason.

If any single player game that allows friendly fire to CPU allies, there is a lot of friendly fire.  That is my biggest beef with COD4.  I want to bust caps in my guys without a stupid warning every time.  

Back in the day, I liked launching rockets at camels in LHX Attack Helicopter.   

In Turok, I loved to corpse juggle with the Alien weapon or the rocket launcher. What made it so great was no mater how many times explosions flung them into the air, they'd still scream and blood would still trail behind them.... good times.

 I was partial to randomly strangling people myself, something I probably enjoy too much.

After you beat Assassin’s Creed you don’t take damage from killing innocents, so I just keep hidden blading entire crowds and naturally the guards never put it together.

I love dying. Seriously, if i'm in a place in the game that looks like i can die i do it on purpose just to see how i die. For example, in mario 64 i drowned on purpose just to see what it would look like (it's so sad), or being killed by the various monsters in silent hill games and stuff.

Oh, I'm the king of doing silly things in games. Where to start?

* Trying to fish for the last boss of Twilight Princess (which actually proved beneficial, oddly enough)
* Doing infinite Spin Attack/Butt Stomp attacks on Luigi's head in SMG (all the more funny since he screams "wah!" every time the spin attack move is activated, successful or not)
* Slicing 3 limbs off a Protocol Droid in LSW, then hopping around on 1 leg with them and having them activate doors
* Repeatedly killing my own party in FFX when all characters have Auto-Phoenix on their shields
* Setting up impractical-but-funny Materia combos in FF7 like Added Cut + Cure
* Flying around various areas of KH1 and KH2 using Glide/Superglide (and floating in place in KH2 with Glide Lv.2 and Lv.3; that's so fun)

And many, many other silly things. One of my favorite pastimes since the NES days has been doing stuff that the game doesn't necessarily expect me to do.

When I first played Sonic Adventure, I would, through Sonic, look at every fine detail, in the glorious 3D levels. Other times, I would play certain games, that I have completed 100%, just get a nostalgic rush, or perhaps, listen to some of the game's awesome music again... Of course I did not spend too much time doing this, for I realise that I have already completed the game, and the game, almost instantly, becomes dull.

That's how i play every Megman game... I didn't think it was weird.

I don't use healing items in RPGS outside of inns. I used to do some really werrid stuff unlike these things. What they were however i can't remember.

I'd often play games without killing normal enemies.  Just boss characters and characters you HAD to kill.  Just for the extra challenge.  I know there has to be better examples though. 

I can use mario's back jump kick in Mario 64 to scale pretty much ANY slope in the game.

I also love juggling enemies in turok

In Thief: Deadly Shadows, I allowed myself to be taken prisoner, then broke out of jail, killed absolutely none of the guards, but I knocked out EVERY SINGLE ONE, and then carried them ALL THE WAY back down to the very cell they had locked me in, and dumped them all in there before releasing every prisoner that could be freed.

If I'm playing an D&D or RPG game that has items, but there are also characters in the game that have healing techniques, I NEVER use items or Inns. I always rest outside and have all my cleric characters heal everyone before resting again.

In Super Mario World, I managed to beat bowser after having only defeated a single castle. castles 2 - 7(or was it 8?) were left completely untouched.