In contrast to John's question, I'm looking for things which could easily happen if only we had the idea, facilitated by technology today, or (even better) with nothing but pen and paper, raising hands, etc.

Think about the difference between small group coordination without the idea of taking a vote, vs with. That's the sort of difference I'm after.

Or driving with/without the idea of staying on the right side of the road.

Or a world with/out kickstarter.

If you want a numerical mark, come up with 20. Ideas can obviously be super vague (EG "like kickstarter, but for Effective Altruism"), since I'm not expecting you to EG actually come up with a better voting system or a way to make futarchic governance practical for small groups, etc.

Feel free/encouraged to list "obvious" ideas, including ideas already mentioned by other people, to keep the creative juices flowing.