lol for an english assessment once, my teacher started writing the amount of seconds left on the board.
anyway, our school doesn't penalise it either, which is kind of unfair.
i usually have a while left... if there's multiple choice, i work out the answers in the reading time so i can circle the answers quickly and have more time for essays.
i'm a really fast writer, too, so i always seem to sit around for ages wondering if i've written enough because no one else is finished... ie i finished section one in my exam today in like 20 mins when the time allowed was 45 minutes. and i wrote detailed answers too, one of them ended up being a page over the lines they'd given... but they were pre-written/memorised answers.