Grammar Police (What ticks you off?)

I work at my college's newspaper and I cringe every time I see bad grammar and/or punctuation on the Internet. (Yes, including LPSG)

Here are some things that tick me off:
1) Not knowing the difference between "every day" and "everyday"

2) Everyone's favorite: your and you're

3) Possessive names: "The Smith's had a party." WRONG "The Smiths had a party." RIGHT!

What are some things that tick you off as part of the Grammar Police?