This has been a pet peeve of mine for some time now. Some misspellings here and there are ok, as are typos but when somebody posts a thread or something and you have to read it a couple times to understand what it says, well THAT ( ) is what I'm annoyed about. Also, run-on sentences. Those annoy me the most. I'm not that annoyed with capitalization, or lack thereof, since you are still able to read the post.

But as said before, some have some sort of medical condition where they have trouble typing properly. I understand that, but when you don't have one and you have english as your primary/first language, then that's when it bugs me. I can think of a few people like this, but I won't mention names.