Usage pet peeve: people who use "literally" to modify something figurative. For example, from a marketing book I recently read: "People are literally bombarded with advertisements in their mailbox every day." Unless the writer is describing Iraq, I don't think that's a literal bombardment.
But in reading a book about Abraham Lincoln's depression, Lincoln's Melancholy, I came across the following description of the raucous reception Lincoln received one week before the 1860 Republican National Convention in Chicago:
"The crowd went wild. Delegates and onlookers threw hats, books, and canes into the air. The wigwam shook so much that its canvas exterior became detached from the wood beams. 'The roof was literally cheered off the building,' declared an early account of the maelstrom."
Now the pleasure of a sentence like the one from the early account is diminished because people don't care enough to know the distinction between literal and figurative. Nuts.