Silicon Power USA via Amazon offers the Silicon Power 1TB Rugged Armor A80 Portable USB 3.0 External Hard Drive, model no. SP010TBPHDA80S3B, for $69.99 with free shipping. That's the lowest total price we could find by $12 and the best we've seen. This drive, which passed the US military transit drop test (MIL-STD-810F 516.5 procedure IV) and waterproof test (IEC529 IPX7), is dust-proof, pressure resistant, and can be three feet underwater for up to 30 minutes.