One wouldn't think that being a second off every, oh, 70 million years or so, would be such a huge deal, right? Apparently that benchmark just isn't timely enough for the National Institute of Standards and Technology, whose Time and Frequency Division has fabricated an experimental atomic clock based on a single mercury atom in favor of the fountain of cesium atoms used now. They've discovered the prototype is even more accurate than the current standard, and would only lose one second every 400 million years. Obviously nobody reading this will even be around in 400 million years (um, right?), but there are reasons to improve aside from holding the time steady: precise time-keeping aids in accurate syncing of GPS and navigation systems, telecommunications, and deep-space networks. We admit, this whole thing leaves us a bit flabbergasted, but the sense of absurdly painstaking scientific security we'll get from knowing that while civilizations rise and empires fall, no one will live to see this atomic clock miss a beat -- well, that couldn't have come a moment too soon.