Stupid hipster 80s fetishism notwithstanding, cassette tapes don't get much love. That's a shame, because magnetic tape is still a surprisingly robust way to back up data. Especially now: Sony just unveiled tape that holds a whopping 148 GB per square inch, meaning a cassette could hold 185 TB of data. Prepare for the mixtape to end all mixtapes.
Sony's technique, which will be discussed at today's International Magnetics Conference in Dresden, uses a vacuum-forming technique called sputter deposition to create a layer of magnetic crystals by shooting argon ions at a polymer film substrate. The crystals, measuring just 7.7 nanometers on average, pack together more densely than any other previous method.
The result: three Blu-Rays' worth of data can fit on one square inch of Sony's new wonder-tape.