At Backblaze, we provide unlimited storage to our customers for only $5 per month, so we had to figure out how to store hundreds of petabytes of customer data in a reliable, scalable way—and keep our costs low. After looking at several overpriced commercial solutions, we decided to build our own custom Backblaze Storage Pods: 67 terabyte 4U servers for $7,867.
Nicely architected 4U storage pods. It's very unusual for a company to explain, in such detail, how they built a core layer of their system. I love that they included the 3D design of the enclosure, as well as a detailed Bill Of Materials list. All of which was really only possible because of the tremendous amount of work tha went into Linux and the Linux storage subsystems.
Let's hear it for Open Source software (and Open Source design)!