You just knew Western Digital would take every chance it could to milk every last ounce of profitability from its extra-spacious 2TB SATA hard drive, didn’t you? After launching the drive for high-end workstations and desktops earlier this year, WD has crammed two of them into a single external drive. The world’s first 4TB external HDD is being labeled the My Book Studio Edition II, which is now twice as roomy as the same drive a year ago. Designed to work with Mac and PC systems, the quad-interface drive can