A little tact goes a long way

How can you tell a friend that they continue to misspell a certain word? The first time you saw this mistake, you thought to yourself, it's a typo. Then, the 2nd time, you think "I'm not a grammar Nazi". Then, I've continued to see the same misspelled word over and over and over. IT.IS.DRIVING.ME.CRAZY. And don't think I'm not the only person to see it. Another friend has seen it and mentioned to me as well. But neither of us know how to politely, tactfully, or graciously mention abovementioned misspelled error to this certain person. Can I hire someone to be a little less tactful to get the point across? Really, I just cannot believe no one else has mentioned it.