Buxley writes "NASA is reporting that they've found the likely cause for last week's loss of the Mars Climate Orbiter. It seems one of the engineering teams was using English units of measurement while another team was using Metric units. Getting this straight is rather important when designing navigation sytems for interplanetary spacecraft, one would think." A lot of people sent this one in; thanks to all. And if this event doesn't prove that it's time for the U.S. to go 100% metric, I don't know what will. Oy!