In an industry where customer churn can be likened to the fearsome troll under the bridge, Sprint has launched a program designed to keep its favored subscribers around for another two years. While not everyone is eligible -- those who've upgraded less than eight months ago, corporate outfits and those in collections need not inquire -- the program lets customers buy their way out of their current commitment and become eligible for a new, subsidized handset. The promotion begins February 12th and is set to run through the 14th of April, where the amount you pay correlates to the time since your last upgrade. So if you're currently pining for the Epic 4G Touch or the iPhone 4S, just give your local Sprint store a call this Sunday. They just may be able to hook you up.