"I don't have my books with me..."

[the phantom]

I usually use the internet at school

I, too, often use the computers at school, so I don't have my books with me for about 90% of my posts.

When I know something from the books well enough to post without looking it up I make sure and say "I don't have my books with me". I do this for two reasons- 1) in case (this hasn't happened yet) I'm completely wrong or 2) to show off my Tolkien smarts (sort of like saying "I don't even need a book to answer that question! Ha ha!").