Headphones

If you're going to disturb my commute, at least have the decency to play "Super Bass" loudly from your phone's speakers so I can appreciate the brilliant lyrical stylings of young Nicki Minaj.  How else will I hear that boom, badoom, boom, boom, badoom, boom bass?
Throwing a book at someone's head is never a good idea. Unless of course you're playing a game where the only way to win is to throw a book at someone's head. Then it's probably a good idea.