We here at The Fictional Café tend to notice when a comma is used when a semicolon is necessary and when a person decides to lay down instead of lie down. Sometimes it makes us pull our hair out, but other times it elicits a hearty chuckle from us.
Fortunately for you and me, the omnipresent eye of the internet notices too. Here are two of my favorite sites for fail-induced guffaws. Oh, and I had to include one great blog for accurate, easy to understand grammar and spelling tips. You know, to balance out the facepalminess.