Walmart offers the Seagate FreeAgent GoFlex 500GB Portable USB 3.0 External Hard Drive, model no. STAA500105, for $49 plus 97 cents for shipping ($0.10/GB). That’s tied our April mention and tied for the lowest total price we’ve seen for any 500GB portable USB 3.0 hard drive. (Our previous mention at this price point was after rebate; it’s also a current price low by $24.) This drive runs at 5400 rpm and features an 8MB cache.