Amazon offers the Western Digital 4TB Serial ATA 6Gbps Internal Hard Drive, model no. WD40EZRX, for $149.99 with free shipping. (B&H Photo and Video has it for just a penny more.) That's tied with our February mention and the lowest total price we could find by $7. It features a 64MB cache and GreenPower technology for lower operating temperatures, low acoustics, and increased sustainability.