Even better is when a long-dead system is suddenly resurrected and repurposed for another project.
I had a friend at a company I left tell me they were un-mothballing a cancelled platform (killed at the time by an unfortunate acquisition) and deployment system I built several years ago because it was needed again. The whole thing was pretty janky because it was barely past prototype but fairly functional.
I wished him good luck and told him to find a new job, because there be dragons. He took the advice eventually, but I did hear they got it up and running again, with some pain. Apparently it is out there chugging along doing its thing once again.
I definitely never intend it to last that long.