Trans Intl. offers the ProStor 635i 4TB eSATA / FireWire 800 / USB 2.0 External Hard Drive for $298 plus $8 for shipping ($0.08/GB). That's the lowest total price we could find for such a drive by $44, although we saw a 3TB model for $120 less last week. This 4TB 7200 rpm external hard drive features an aluminum casing, 64MB cache, eSATA and USB 2.0, FireWire 800 port, and FireWire 400 port.

Note that this drive is designed to fit under an iMac base, but can be used with any Mac or PC.