In the real-world, reselling used books and CDs is not only legal, but the way most of us got through college. But what does a re-sell Model look like in the virtual world? EMI's Capitol Records is currently seeking an injunction against ReDigi, a start-up that claims to sell "used" digital tracks. The site scans user's hard drives to make sure their digital tracks were bought legally, lets users upload them to the site, and then erases the track from their hard drive. The technology is both ing...