MrSeb writes "Hot on the heels of the most successful storage mediums of all time — MiniDisc and Zip disks — Sony has announced the Optical Disc Archive, a system that seems to cram up to 30 Blu-ray discs into a single, one-inch-thick plastic cassette, which will have a capacity of between 300GB and 1.5TB. As far as I can tell, the main selling point of the Optical Disc Archive is, just like MiniDisc, the ruggedness of the cassettes. Optical discs themselves are fairly resistant to changes in temperature and humidity, and the cassettes are dust and water resistant. What is the use case for these 1.5TB MiniDiscs, though? In terms of pure storage capacity, tape drives are still far superior (you can store up to 5TB on a tape!) In terms of speed and flexibility, hard drives are better. If you're looking for ruggedness, flash-based storage is smaller, lighter, and can easily survive a dip in the ocean. The Optical Disc Archive might be good as extensible storage for TV PVRs, like TiVo and Sky+ — but as yet, we don't even know the cost of the system or the cassettes, and I doubt either will be cheap."