Eats, Shoots and Leaves - Lynne Truss

A panda walks into a cafe. He orders a sandwich, eats it, then draws a gun and fires two shots in the air. "Why?" asks the confused waiter, as the panda makes towards the exit. The panda produces a badly punctuates wildlife manual and tosses it over his shoulder. "I'm a panda," he says at the door. "look it up." The waiter turns to the relevant entry and, sure enough, finds an explanation. "Panda. Large black-and-white bear-like mammal, native to China. Eats, shoots and leaves."

So, punctuation really does matter, even if it is only occasionally a matter of life and death.