The Western Digital Passport is a reasonably popular line of external, portable hard drives. The company keeps upping the storage capacity, and the latest offering is all the way up to 320GB. The 2.5-inch portable drive weighs only five ounces and has the protective inner workings you would expect and hope for from a portable drive. If this drive is like the others in the Passport line then the one thing you will want to look out for is the USB cable.
They provide you with a cable that is inconveniently short, but which is thick enough to provide the required power consistently. As you have probably encountered, getting enough power via USB is not always easy. There are all sorts of reports of problems by users who try to replace that cable with a more usable length. If you can overcome that little problem this drive provides reasonable value in an appropriate situation at $230.