After using hundreds of thousands of hard drives in their quest for world domination, Google knows a thing or two about spinning platters. All of their hard work has been distilled into one academic paper describing correlations between hard drive age, manufacturer, and data density.
The most interesting finding? SMART, the system used to test hard drives for imminent failure, is all but worthless and there is no direct correlation between active usage and potential failure.
Google Labs [via SlashDot]