I heard that Lightning, internally within the network, can define down to .001 satoshi. 1/1000th of a sat.
If we could harness that resolution
If we could charge "sub sat" levels when assessing fees, the thought might become more acceptable. You are paying, but nothing to speak of. Maybe a tenth of a sat.
See, the problem for me would be is paying a sat for a notification that I had been zapped 1 sat!
I actually get 1 sat zaps from time to time. I like them.