After traveling the world for almost 2.5 years, I've become pretty knowledgable, mostly through trial and error, about which technology is useful to bring along during a trip and which should simply stay at home. It's not always obvious, as evidenced by about 2 pounds worth of technology currently in my suitcase which I haven't made use of in a long time. But one item that I've found practically indispensable is a portable external hard drive, especially since many of the new laptops (such as my Macbook Air) have a limited amount of built-in SSD storage. WD My Passport The best external hard ...