Samsung Spinpoint F3 HD502HJ 500GB 7200RPM (500GB/Platter) Hard Drive for $49.99 shipped after coupon code TRICKORTREAT.  Here is a screenshot for your reference.  Note that it is in OEM packaging, which means no pretty retail box, but is otherwise identical.  This is part of the the latest F3 series, which utilizes a 500GB/platter, the highest density currently available for reduced power consumption and better performance.  Most places have it for over $55.