I just bought 2 TB in four 500 MB drives for less than $430 including shipping (that's an improvement from $150 per MB in 1979 to about $0.22 per MB**). With the great tools now available on most motherboards, I arrayed these in a fast and redundant Raid 0+1 setup with 1TB of storage. (Yes, to the total geeks out there, I would have preferred Raid 1+0 but alas the Nvidia chipset on my board did not support it.)
** By the way, this 700x improvement over 30 years actually has little or nothing to do with Moore's law. While some of the materials sciences are related, this improvement has little to do with silicon and nothing to do with transistor density. This is the result of incredible human creativity in the face of brutal competition, both from other hard drive manufacturers as well as from substitutes like static RAM.