I'm in the unfortunate phase of my "homelab" where I have about 300TB of storage spread amongst 3 continents. Civilization will fail before I lose all of my data.
Old cable TV and satellite boxes often have hard drives, I think I used to find 500gb drives in there. But they have TONS of usage. I think I paid $1-2 for them.
Yeah, old DVR boxes were pretty fantastic when you just needed a lot of storage. They were one of the few places you could reliably find 1TB drives, back when those were still fairly new and expensive.