I write a lot. Professionally speaking, I'm always writing white papers, press releases, articles, marketing copy, education guides or plain and simple web site copy. As a hobby, I'm writing here. I spend a solid chunk of every day writing, and when you throw a double major in English and History in the mix, I've been doing so for well over a decade.
There are two words I've always mistyped, and I'm not sure why. I know how to spell these words, they're simple words, but my fingers go into autopilot and type a completely different word. These words are "alone" and "say".
Often when I mean to type "alone", I type "along". Even now I had to consciously think about the keys I was punching to make sure I got it right. When I mean to type "say", it often comes out as "saw". Spell check doesn't help, as I'm mistyping a legitimate dictionary word. A wire gets crossed and alone becomes along and say becomes saw.
Strange, but true.