Spell-checkers are a huge distracting pain. My first official act on any kind of text-producing equipment is to turn the damned things off.

For typos and suchlike, I know I ought to run them manually before going public with anything - HN comments included - but usually I either forget or can't be bothered, because I know the real errors will drown in a sea of red underlining - me using strange words or simply writing in another language than the checker is set up to expect.