Looking for mass storage on a budget? This company has outlined an easy-to-follow, and affordable way to built a peta byte storage server. The server is basically a custom designed 4U rackmount chassis with hard drives filling almost every square centimetre. They also added 2 power supplies and plenty of fans to cool down the whole setup.
From what I can gather, the server offer semi hotswap functions. The power supplies work in tandem to power-up everything, and I want to think that if one spends more money, you could add 2 (or 4 low profile) hot swap power supplies to the setup. The SATA hard drives should be hot swappable, but I guess with the metal housing it could be a bit dangerous.
Still, it offers a lot of space on a small budget!
The full story can be read here: http://blog.backblaze.com/2009/09/01...cloud-storage/