Western Digital Caviar Blue 500GB 7200RPM Interal Hard Drive for $48.59 Shipped

Western Digital Caviar Blue 500GB 7200RPM Internal Hard Drive for $48.59 shipped after coupon code WKF35JP9FR9BLQ.  Here is a screenshot for your reference.  It uses a high-density 2-platter design for better performance while reducing power usage.  Note that it comes in OEM packaging, which means no pretty retail box and marketing materials but is otherwise identical.