Even better. Discreet (later acquired by ADSK) used to ship proprietary RAID arrays for use on SGIs with their high-end editing systems. They had this smart thi

Even better. Discreet (later acquired by ADSK) used to ship proprietary RAID arrays for use on SGIs with their high-end editing systems. They had this smart thing where frames of larger sizes would be placed on the outer tracks of the platter for faster reading/writing - one of their promises was "if you press play, it plays" - and it always did uncompressed. What they did is a custom filesystem ("stonefs") that you had to use, the disks would not be formatted with xfs but instead with that proprietary filesystem. Now here is the tasty bit: the replacement hard drives they would provide themselves as well. Apparently, the "proprietarization" of a disk for such an array involved overwriting a few sectors of the disk with custom magic bytes so that the stonefs formatting software would accept it as "native". Obviously when disks in arrays would die, and the array would be too old to support, those disks would become unobtainable. I knew (via via) of a guy who could "flash" an off-the-shelf disk with the magic bytes so that it be recognized as a proprietary stonefs disk. Luckily they developed a system for frame-addressable storage on standard filesystems in parallel, and when they decided to step off the "proprietary hardware" story all they had to do was enable it. Now it's just a directory structure.