In a nutshell: The entirety of Microsoft's Xbox Game Pass subscription service for the Xbox One can apparently fit on a single external hard drive with room to spare. While most people probably won't go through the trouble of downloading every single title, we now know it is possible with the right storage drive.
In testing Western Digital's WD_Black D10 Game Drive, Kotaku's Mike Fahey decided to download every game available on the service, which turned out to be around 250 titles. He said the process took roughly a week and his ISP wasn't happy, but ultimately, everything fit on the 12TB drive and he had around 7.5 terabytes of space remaining.
For those interested, Western Digital's 12TB Game Drive for Xbox One features a 7200 RPM drive in an external enclosure with active cooling. WD notes the drive is rated at (read) speeds up to 250MB/sec and can hold up to 300 games (with each game averaging 36GB).
The unit includes two 7.5W Type-A charging ports, which can be used to charge other accessories, and can be positioned either horizontally or vertically. It comes backed by a three-year warranty and includes all of the cables needed to get up and running.
Earlier this month, we learned that it would cost a little over half a million dollars to acquire every bit of content on Steam's digital platform.