I don't. Although I can easily fill up a terabyte drive, little of that is my own personal files that I need to keep if the drive blows up. Most of my stuff is source code, documents/notes and some photos (with photos being the only thing that takes up significant space). Almost everything else I can re-download or rebuild from the original source as and when I need it.

In total, sure, but at least for myself the really important stuff would fit in 10MB and I think I could fit all of the medium importance stuff in 1GB. The remaining terabytes are nice-to-have but I wouldn't be too upset if I lost it.