WD My Book VelociRaptor Duo review | Disk drives (hdd & ssd) Reviews | TechRadar:

"It's been over nine months since Apple introduced Thunderbolt, and the port has gradually been rolled out across the range. However, Thunderbolt peripherals, including drives, remain relatively rare.
With the My Book VelociRaptor Duo, Western Digital has taken two of the fastest drives it makes, with a SATA 6Gb/s interface and disks rotating at 10,000RPM, and put them in a similar enclosure to its Thunderbolt Duo drive. And it certainly is fast."

WD My Passport Edge External Hard Drive Review - HotHardware:

"When USB flash drives first came to market it was a revolution. They offered much larger storage capacity compared to floppy disks, packaged in something about the size of a person’s thumb. Suddenly, you could just save your papers, presentations, and even a smattering of photos onto a little flash drive and safely take it with you anywhere."