I've spent a lot of time thinking about this, especially when I was a bookseller with a used section in the store. We had a lot of collectors who'd take great pains to read their ephemeral paperbacks carefully so as to give no sign that the book had been read at all, so that they could maximise the theoretical future value of the book once it became collectible.
I've always been depressed by this approach. It requires that you treat the object as a "future collectible" instead of a "present utility," which means that you rob your present to pay your future. What's more, you end up leaving out the collectible value that arises from the texture and wear on the object when its value rebounds (see, for example, this worn first edition of Neuromancer from the Merrill Collection's stacks in Toronto).
What's more, if all ephemera were preserved like this, it would never rebound, because it would never become scarce. Apple ][+s have collectible value because not many are left. If they were as common today as they were in 1981, they wouldn't be a collectible -- they'd be junk.
So the only way to convert ephemera to collectibles is to use most of it up. This essay is a great theoretical framework for understanding these issues.
The Trough of No Value
For some objects, what pertains would more accurately be called a trough of low value, not no value–remaindered photo books and certain old cameras come to mind–because they never actually quite reach zero value. But other objects might accurately be graphed considerably below the $0 line–those would be things that are worth nothing but that require maintenance, expense, or storage space to keep and preserve. My great-grandfather's sailboat, for instance–a gorgeous 29-foot sloop made of cedar and mahagony that was originally built for Civil War General Lew Wallace, the author of Ben-Hur. It's currently being stored at considerable annual expense by a cousin who's into historic preservation, but it's worth no money in its present condition. Graphed, I imagine it would fall well below the $0 line.
My favorite example of the Trough of No Value comes from a former acquaintance whose back room had a high, narrow shelf running all the way around it, about a foot below the ceiling. Arrayed on the shelf were dozens of kids' lunchboxes from the 1950s and '60s. He told me that not only are such lunchboxes collectible now, but that they're actually fairly hard to find. Time was, of course, when most every schoolkid had a little metal lunchbox (poor kids "brown-bagged it"). But the kids grew up, the school lunch program got started, and who wanted to keep old lunchboxes around? They weren't useful any more. They weren't worth anything. And, since they were almost all used for their intended purpose, many were damaged or worn by use (I vaguely remember owning one that was rusty and had a dent). People naturally threw them away. The "trough of no value" for lunchboxes was long and harsh. That's why they're not so common today as you might guess–because not that many made it through the trough. (By the way, the inset photo is a corner of Allen Woodall's Lunchbox Museum in Columbus, Georgia.)
I write books. My latest is a YA science fiction novel called Homeland (it's the sequel to Little Brother). More books: Rapture of the Nerds (a novel, with Charlie Stross); With a Little Help (short stories); and The Great Big Beautiful Tomorrow (novella and nonfic). I speak all over the place and I tweet and tumble, too.