Do you know how much an atom weighs? A nano-pound? Maybe a nano-ounce? Physicists at the University of California, Berkeley, have come up with a way to weigh atoms. These researchers have used a carbon-nanotube-based nanomechanical resonator to weigh an atom. The device is a special mass spectrometer that is more sensitive. What's going to be next? Read the article abstract on Nature Nanotechnology here.