Western Digital VelociRaptor 150GB 10000 RPM SATA Internal Hard Drive for $139.99 shipped after this $20 rebate. Here is a screenshot for your reference. Note that it comes in OEM packaging, which means no pretty retail box but is otherwise identical. For the technically inclined, it has a rotational speed of 10000 RPM and very fast seek time of 4.2ms vs about 9ms for most SATA hard drives. Most places have it for $159 or much more.