B&H Photo-Video offers the Hitachi Deskstar 7K4000 4TB Serial ATA 6Gb/s Internal 3.5" Hard Drive (click through to B&H), model no. 0S03355, for $189 with free shipping ($0.05/GB). That's the lowest total price we've ever seen for a 4TB 7200 rpm hard drive by $11. (It's also a current price low by $66.) It runs at 7200 rpm and features a 64MB cache.