I guess I would have to say that grammatical errors only bother me when I'm reading something that really should NOT have such errors. When I'm reading e-mails from friends, or things posted here in the forums, I really don't care as long as I can figure out what the writer is attempting to say. (And it kind of intimidates me to realize that we're under such intense scrutiny here.

)
On the other hand, one of the funniest grammatical errors/typos I've ever seen was at my own expense, although not my error. I had an essay published in a book of knitting stories, and all of the author bios were in the back of the book. My bio was supposed to have the line, "Jack of all trades but master of none," but because of a typo it actually said, "
Hack of all trades but master of none." The version with the typo is much less boring, right?