Almost a million years ago, when i was in the army, i had to sit a Signals exam. One question was, "What does IPA stand for?" I was the only one in the class who got it correct - Indian Pale Ale which, of course, has absolutely nothing connection with Signals. However, i had been forewarned that the question would be there by someone who had sat the test 2 days before. Apparently, each year a different rogue question would be included in the test paper just to concentrate the minds of those sitting the exam.