There used to be a little web site where you'd fill out a little form that asked you how much data you had, and it would provide a list of commercially available hardware that could be bought or configured to handle it on a single machine. I think it would even give you a link to someplace you could order that piece of hardware.

This reminds me of the time, way back when, that a coworker told me about how our customer was filling a rack with a terabyte of hard drives. My eyes bulged a little bit to think of it. Now I chuckle to think that the laptop I had two laptops ago had a terabyte drive in it.