Curious About Other Proofs of Work ( Or Things Like It ) - Blockchain

I am just starting to try and understand Crytocurrenty and Blockchain technology, I completely understand we are likely past the point of the swings and speculation that were all the rage last summer but I am total new so please cut me a a break on my ignorance. I have only been at this for a week and I am trying to understand other applications and intricacies of the technology.

Specifically I am trying to understand if there are folks out there who have developed other interesting ways to add layers to Blockchain outside of mining. ( Like Steemit and its community of contributors )

I want to research other types of Proofs of Work outside of the Mining that has made the traditional Coins famous because I get the sense there are other interesting ways to contribute to humanity through blockchain that forgo the costly methods of mining currently being performed. This week I saw articles lamenting the amount of energy and processing required to mine a coin which could spell trouble with rising energy costs.

To understand this I mined a couple tiny fractions of monero based on this article : https://hackernoon.com/mine-for-bitcoin-with-any-computer-9a30337843e7

It became quickly obvious what I thought was a pretty powerful machine in not suited for the work. You really would need to build a high speed machine which would end up heating bathwater like this guy : https://motherboard.vice.com/en_us/article/9k8ykp/heating-water-with-bitcoin-mining-asic-reddit

(Note, as a maritime engineer we find ways to reuse heat/energy all the time and thought it was bad @$$ this guy found a way to re-use his mining heat. However, us maritime types while recovering heat sometimes understand recapturing the energy already spent is sometimes more hastle than its worth.)

I understand that Steemit has replaced Mining with Subjective Contributions by trying to give incentives for people like us to participate in a community. From Steemits own white paper it states :

"In the case of Bitcoin-style mining, it can result in the production of specialized hardware and cause people to invest time developing more efficient algorithms. It may even help find prime numbers, but none of these things provide
meaningful value to society or the currency holding community at large"

I think its really cool there is location on the Internet that has found an alternate way to foster dialogue on the internet while participating in Blockchain. Has anyone else out there come across other Proofs of Work that are different ways to perform the same funcationality?

Thanks, feel free to engage or correct me if I am totally off.