Walmart offers the Western Digital 1TB Black Series Serial ATA 6Gb/s 3.5" Internal Hard Drive for $72.99. Opt for in-store pickup to drop the price to $48.57. That's $2 under yesterday's mention, the lowest price we could find by $21, and the best price we've ever seen. It runs at 7200 rpm and features a 64MB cache.

A close price: Amazon offers it for $49.56 with free shipping.