You know you're a grammar Nazi when you read the above and realise that:
1) flamebirde was correct; it's "you're"
2) Brainiac probably didn't realise that everyone else would misread brainy's 'One-Up Me' and assume that brainy was incapable of correcting sentences
3) flamebirde has become self-conscious about writing a forum post because of brainy
4) marksmanjay's re-correction of flamebirde's statement is oddly funny
5) EDM didn't put a period after each point, and will not do so as she is not a grammar Nazi
6) EDM has referred to herself in 3rd person while typing these points
7) marksmanjay, flamebirde, brainiac100, and EDM show up as grammatical/spelling errors when typing (the computer doesn't categorize them, apparently)
8) 'realise' comes up as a spelling error in US english, but not in UK english
9) 'english' comes up as an error as the 'e' is not in capitals
10) brainy is not considered as a spelling error, though many would disagree with me (I really don't know why)
Edit: just to check my work...
^ The sentence above contains grammatical errors. However, this sentence is free of any errors, as per the computer spell-check.