In a shared house for this year of university- and I made the mistake of selecting the front, ground floor bedroom (what should have been the living room). Upon choosing this room, and moving all of my stuff in- I have somehow got fucking 'concierge' stamped on my forehead.
My housemates are lovely and we get on well. However, I have a serious bugbear with them: they expect me to keep on opening the door for them.
They are repeatedly losing keys, then finding them, then someone else loses them. As my room is right next to the front door, it's me who has to stop in the middle of my sentence for my essay, or quickly blow on the nails I was painting, and go and open the door for them.
This is a minor aspect of my problem- I wouldn't ever leave someone outside who genuinely didn't have a way of getting in, but because in the past I have previously jumped to look after the poor dear who left their keys by the toaster and are now locked outside in the rain, they almost expect me to run and open the door for them- rather than letting themselves in the house.
For example, someone will ring the door, I'll ignore it, they'll ring it repeatedly a few times to attempt to get my attention, I'll ignore it again- and then they'll give up and let themselves in. WHY DON'T YOU JUST GET YOUR KEYS OUT AND LET YOURSELVES IN INSTEAD OF WAITING FOR ME TO DO IT?
Sometimes they just choose not to take keys out. Which is great for them not having that ridiculously heavy key chain taking up valuable lipstick and fag space in their clutch bag, but not when the bloke they copped off with kicks them out before his lecture and they're there bashing the door down at 8am waking me up.
Last night they all went out as house, and I stayed in as my boyfriend was over for the weekend. Naturally we both took advantage of the quiet, but I was furious to hear 'DING DONG DING DONG DING DONG' at that vital moment 
- when I pulled myself off him, chucked a dressing gown and opened the door- 75% of my housemates were stood there looking gormless and explained that that the only person with a set of keys had gone to buy some mushrooms. HOW HARD IS IT FOR ALL OF YOU TO TAKE YOUR KEYS WITH YOU?
This sounds horrendously trivial, but it's happening everyday and I've had it up to my tin lid. I've got mixed opinions, some people are saying that IABU because in my family home you would just go and open the door to anyone who knocked, and some people think that I'm right and they're just taking the piss.
Haven't seen any of them since they rudely interrupted my orgasm. I just flung the door open, snarled (yes, a real live snarl) and stomped back to my room.