A classic of the obsolete things these days is the Rolodex paper file system.
Simple lines and good usability but no real remaining value in digital times.
We read on the web1, that:
In 1954, Hildaur L. Neilsen, an employee of Arnold Neustadter’s Zephyr American Corp , invented a rotary card filing system much like those seen on desktops today. The product was brought to market in 1958 as the Rolodex.