[nerpderp83]

This would have been a godsend for managing inventory.

In a somewhat related idea, is that of unioning the footprint of alternate parts in a PCB design so that either part could be used. I have never used any high in EDA software, but if you had end to end design, schematic, pcb layout and parts databases with high level machine-readable symbolic pin descriptions, these could be inferred automatically (unioned footprints).

Using your idea, I wonder if you could automatically have "hot standby" components in the same package?