This is probably the most promising invention yet! The Rodin Coil has the potential to be a free energy generator, an end to most if not all disease, and an interstellar drive. All of this is theoretical, but there are people doing independent, open-source research. However, I personally, can't understand any of the mathematics behind it.

https://thegoodhuman.com/what-is-a-rodin-coil/
https://www.endalldisease.com/rodin-coil-complete-guide/
https://vid.puffyan.us/watch?v=9RJTLMBW2zM