You forgot proof of burn. The biggest one after pow, pos or proof of stake time.
Well, Proof of Burn is currently used only by
one small altcoin (and another one that's probably dead) so I don't consider it a "big" algorithm
Nevertheless, I'm a strong supporter of PoB, because even if it cannot be used as a standalone algorithm it complements PoS and PoW well.
At the second one real files are shared, and those files are the stake.
That is one of the "holy grail" algorithms ("algorithms that would satisfy a real-world need"). But until now, I considered it to be impossible to use as a
consensus algorithm - or at least a really big challenge. I know there are projects like Sia, but Sia uses PoW for consensus, the "proof-of-storage" rewards are bonuses paid by the storage users (I think they called them "renters").
Can you point me to projects that are using this kind of algorithm for
consensus? Serious question. I know that Burstcoin is trying to develop such a thing, but last time I checked it was only a promise or long-term goal.