(posted at 11:40PM BST) 
I currently have around 800Gb of personal storage at home - spread over a 335Gb RAID-5 array on my SMP box, a 120Gb RAID-1 array on my Linksys NSLU-2, 160Gb on my Biostar iDEQ 300-MCE, 160Gb on my 17" iMac G5 and the 60Gb on my laptop.
Do I really need it all though ?
I have a complete local mirror of the Fedora Core development tree, dedicated build environments for at least four different Linux distros, my entire CD collection ripped to FLAC and more besides.
I ask the question as I'm currently spec'ing online storage for some new projects that are scheduled to go live in 2007.
First and foremost, redundancy - storage must have dual power supplies that can be fed from my dual rackmount 2200VA UPS units, plus, I must also have two of them - and, the array configuration must be at least RAID-5.
That covers me against UPS failure, storage unit failure and data loss through the failure of any individual disk... so far, I'm doing great on the redundancy front, multiple transit providers, two border routers, two switches, etc, etc.
The benefit of going with disk arrays is that I can buy shitloads of low-capacity drives and via RAID-5 make them into a much larger volume - with reads being striped across multiple drives, the average seek and transfer times go through the floor!
The eventual goal is to have around 500Gb of RAID-5 storage on each disk array but the pair being synchronized using DRBD - therefore, each array will be an exact clone of the other - technically RAID-1, albeit in software but guaranteeing a redundancy equivalent to RAID-10.
I figure I can do it all for less than a grand as well ;-) | 
