Windell writes – “When I was a kid, I read in a science book about how to make a directional compass. You magnetize a sewing needle and balance it on a cork floating in a bowl of water. Even today, this is the standard story. For example, How Stuff Works still says that this is how to make a compass. (There are a lot of other examples, too.) It turns out that it’s a whole lot easier than that. All you need is a really good magnet. “ [via] – Link.