[Question] What are examples of perennial discoveries?

Quotes are from a private mailing list I’m part of. I asked the author if they wanted acknowledgement; I’ll update if so.

Definition of “perennial discoveries”: “These are science or engineering ‘breakthroughs’ that get announced in the press over and over and over, yet almost always fail to reach large-scale commercial use (the failure often not being reported).”

Motivation for asking: “I think it would be significantly easier to make sense of the world if there were a convenient, well-known list of ‘perennial discoveries’. [...] A story on the list could be safely assumed to be unimportant, at least without much more information. Conversely, a story not on the list could be much more important than it might initially seem.”