I suppose we all have our pet peeves. I hate seeing people use 'loose' when they mean 'lose'. Someone already mentioned the boarder vs border. I have a friend who constantly uses 'mute' when she really means 'moot'. I really have to bite my tongue not to correct her. The one that really drives me nuts, though, are emails that read along the lines of "How r u?" I understand text messages were once charged differently, but I think most have unlimited text and my phone provides auto-fill. I always feel like just deleting those messages with no response.
After saying all that, I recognize that I'm not the world's leading expert on spelling or grammar but it seems to me that some people don't even try.
