I must be more cranky today, because now I want to play! I didn't when I first saw this thread yesterday.
First, a pet peeve of mine that I've increasingly noticed myself doing . . . overuse of exclamation marks. Does a sign in a campground about how much firewood to use REALLY need an exclamation mark at the end of each sentence? Unfortunately, I've started doing this more and more, especially online when trying to get across my excitement. I'm an exciteable person and it's difficult to convey that with just words.
Overuse of quotation marks. This one really, truly makes me feel like the top of my head might blow off, although I'm not sure why it bothers me so much. Especially when it's in a context that I can't imagine why someone would use them - like if I had said, "I must be more "cranky" today." There is no reason for those quotation marks, dagnabbit! I did once see a misuse of quotation marks that struck me as extremely amusing, though. In Haines Junction, Yukon, there is a sign on a building on a back road for the Museum "of" Nostalgia. Yup, only the word "of" is in quotation marks. Oh, it cracks me up.
Misuse of apostrophes - as stated by previous posters.
Any number of misuses of words, malapropisms, eggcorns (apparently that's what they're called), etc. A few examples:
"Whenever I was young" instead of "when I was young". You were only young once, it was NOT a recurring event.
The previous poster's example of "for all intensive purposes" instead of "for all intents and purposes".
I've only ever seen one person do this, but he types "Oh so" instead of "also". For example, "I want a green one, and I oh so want a blue one." I thought at first it was a novel and barely acceptable (to me) way of saying he REALLY wanted the blue one, but further evidence has led me to realize that he actually thinks the word "also" is spelled "oh so". It makes me especially sad because he's about 15 and homeschooled, so I imagine nobody's ever corrected him. And I'm too chicken to do it, for fear I'll hurt his feelings. Sigh.
"The worse part of it all" instead of "the worst part of it all". I'm not even sure that this is completely incorrect, but it makes me nuts anyway.
"Thunder and lightening" . . . okay, actually, I find this one a little bit funny, because sometimes lightning makes your hair stand on end, as if it's making it lighter. But still, it makes me twitch.
The previously mentioned moot/mute, amok/amuck, except/accept, and lose/loose. The last one makes me laugh while I cringe, because it's usually a funny image to me - like if you loose your keys, your keys might be out there, running amok, after you foolishly loosed them on the world!
Also previously mentioned, but this one really bothers me, is the misuse of "literally". The use that bothered me the most (because I have a weird thing about eyes and a very active visual imagination) was "my eyes literally popped out of my head". This is the only one of my pet peeves listed so far that I've ever actually mentioned to the perpetrator. I told the seventeen-year-old that it is a terrible abuse of that word to use it in that way - it's basically the opposite of what it means. He replied that that was the point. I think I might have hit myself on the head and made strangled, inarticulate noises. Sigh.
There are two more that previous posters mentioned that I also have to second. People that go out in public when they're sick make me a little nuts. People that take pride in their work ethic because they go to work or school even when they're sick make me at least twice as nuts. You mean you're intentionally exposing me and all those around you to your nasty germs, that you know you have, and we're supposed to pat you on the back for it? Give me a break!
Anything that makes my socks wet. Stepping in a drop of water on the floor, stepping in a puddle, going over the top of my boot (or my hip-waders), being out in the rain for so long that it runs down into my boots. This (for some totally weird reason) reminds me of the feeling of poop in my pants. That's why it bothers me so much (I pooped my pants at about 4 years old, and I've never forgotten that disgusting feeling. Ugh.). A friend made the joke that when it rains on a work day (when I'm working outside), it's like God pooping in my pants. That cracked me up . . . but I still hate it.
Finally, having to put my hands in cold dishwater. My husband used to put dishes in a sink full of water and leave them to soak, sometimes for more than a day. Then I would start to feel like I should do dishes, or like it was my turn, or what-have-you. If I went to the sink, and there was (shudder) cold dishwater in the sink, I just wouldn't do them. I once asked my MIL to pull the plug for me, which she did. I think she didn't mind too much, because I clean the drain in her tub when I go there - she HATES cleaning the drain. So we trade.