I came across this program while checking the warranty status of a bad hard drive. The hard drive was not under warranty, but Western Digital’s website pointed me to their upgrade program for hard drives. Whether the hard drive is under warranty still or not you can receive a discount toward a new hard drive directly from Western Digital. All you need is a valid hard drive serial number; you don’t even have to send in the old / bad drive. If the drive is still under warranty, however, the warranty on the old drive is voided. Also, you can only upgrade the same type of drive: internal for internal, external for external.
I checked the prices on these upgrade drives and they were $10 or more cheaper than prices at newegg.com or buy.com. I opted for a 1 TB Caviar Black and it cost $79.99 plus tax and shipping. I think this is a good program because it gives you an option for replacing an out of warranty drive at a discount.