Trans Intl. offers the ProStor 750GB eSATA / FireWire 800 / USB 2.0 External Hard Drive, model no. 725, for $138 plus $8 for shipping. That’s $0.19/GB and only $20 more than our mention from last week of a 500GB version of this drive. It’s also the lowest total price we could find for a portable quad-interface hard drive of this size and speed. This 750GB 7200 rpm external hard drive features an aluminum casing, 16MB cache, eSATA and USB combo port, FireWire 800 port, and FireWire 400 port.