Easiest filter in the world to write. I don't speak any languages that don't use Latin characters. If the domain isn't Latin characters, I can't read what's on it, block it.
My newsletter fairly regularly gets bounced because of "misspelling" in the subject line. It's called an abbreviation, people. Key on misspellings in the body, but subject lines are like Tweets: people routinely abbreviate so the recipient can see the whole subject in their typically-shortened inbox view.