I can be a bit of a spelling and grammar tyrant too; having both parents and a sib who teach will do that to a person. A few years back I made a list of those common contraction mistakes alongside the proper forms for my kids, and in between I sketched a pretty glum-looking Harry Potter. I told them that those mistakes made him sad.
Speaking of HP and grammar nazism, I was in an LFR the other day when someone asked the person correcting them, "What are you, some kind of spell nazi?" I couldn't resist and asked if they meant a spell nazi like "It's leviOsa, not leviosA." Someone got it and told me "You win." That made my day.
