Western Digital Caviar Blue 500GB 7200RPM Interal Hard Drive for $49.99 Shipped

Western Digital Caviar Blue 500GB 7200RPM Internal Hard Drive for $49.99 shipped after promo code EMCLVNW34.  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.