Today only, until 1 pm ET (or sold out), Amazon offers the Seagate Expansion 1.5TB Portable USB 2.0 External Hard Drive, model no. STAX1500100, for $99.99. With free shipping, that's $0.07/GB, $4 under our June mention, and the least expensive portable 1.5TB hard drive we've seen. (It's also a current price low by $20.) The enclosed 2.5" hard drive operates at 5400 rpm.