Groupon offers the factory-refurbished Western Digital My Passport 500GB 2.5" Portable USB 3.0 External Hard Drive in Black, model no. WDBKXH5000ABK-NESN, for $46.99 with free shipping ($0.09/GB). (Grassroots Computers via Amazon charges the same.) That's $23 under last summer's mention of a new one and the lowest total price we could find for a refurb by $8. It features automatic, continuous backup and password protection. A 6-month Western Digital warranty applies. Deal ends July 26 at 1 am ET.