Heavy-duty filing cabinets with the drawers on ball bearing rollers - the ones like the government used to use. I saw one at the local Goodwill for $20 recently but didn't need it since I've already got enough, but the manager said they had a couple more in the back and they get them frequently. I guess its because youngsters don't keep paper copies of anything and when grandma dies they take stuff to Goodwill. When I was going to government auctions I was always surprised (but shouldn't have been) that younger people always bid higher for the newer, better looking, and much flimsier, metal cabinets and filing cabinets than for the older, but built like a brick outhouse ones.
