Intermittent computing has been interesting for a while to me. I've been thinking of how some technologies used today have implemented the technique of harvesting small amounts of energy to perform some operations required for a given task.
See for instance iLOQ, they provide locks/keys that are authenticated through harvesting energy from a user simply inserting the key, and in that time authenticates if the user is the owner of the lock [1].
I wonder where there are more products like these...
[1] https://www.iloq.com/en/