Help me out Steemit Hivemind! What are the best Altcoins that have some societal or environmental benefit?

As Bitcoin and cryptocurrencies see a huge spike in media coverage this week and going forward, there will be a lot of coverage of the fact that Bitcoin mining uses a ton of electricity and therefore has a large environmental footprint. Obviously gold mining and the printing of national currencies have negative impacts as well, so Bitcoin isn't alone here. As a fan of Gridcoin and SolarCoin, I've long been interested in Altcoins that are better in terms of their impact. Gridcoin uses meaningful computations that benefit research on things like cancer, diabetes, astrophysics, SETI, mathematics, and more. SolarCoin incentivizes the generation of solar energy.
So what other coins have similar benefits for society and the environment?
Steem, Curecoin, Golem, Einsteinium...?

I'll try to keep updating this post based on feedback and then use this for future reference. Descriptions below are from the linked website. I'm not an expert on all of these and can't verify their accuracy.

Gridcoin: http://gridcoin.us/

"Gridcoin is an open source cryptocurrency (Ticker: GRC) which securely rewards volunteer computing performed upon the BOINC platform in a decentralized manner on top of proof of stake.

BOINC is an open-source volunteer computing grid which combines the processing power of all individual users for the purposes of scientific research. It's free, production ready and many projects already harness volunteered computing power to attempt to cure cancer/AIDS/Ebola/malaria, map the Milky Way galaxy, crack Enigma machine codes, etc.."

SolarCoin: https://solarcoin.org/en/node/6

"SolarCoin is an alternative digital currency that works like air-miles for Solar electricity generation. SolarCoin is claimed by individuals living in homes with solar panels on their roof or commercial solar electricity producers. Solar energy, unlike fossil fuels, does not place excess heat or carbon into the atmosphere. The goal is to provide an incentive to produce more solar electricity globally by rewarding the generators of solar electricity. SolarCoin is intended to shift the cost of electricity, thereby reducing the payback time of a solar Installation. In working closely with the solar industry, the SolarCoin Foundation, with SolarCoin, is at the base of a virtuous circle, creating an uptake for solar equipment and helping create jobs in the Renewable Energy sector. Each SolarCoin in circulation represents 1 Mwh of solar electricity generation."

CureCoin: https://curecoin.net/

"Network security from hashing is good. Making money is great. Curing Cancer, Alzheimer’s, Huntington’s, preventing viruses, and designing next-level pharmaceuticals is awesome. What if we could put these together, to build a coin secured and run by crypto, mined with SHA256, and supported by cancer-curing research?

Announcing Curecoin

What benefits does it provide?

Most currencies are either in the CPU/GPU stage, or in the ASIC stage. Curecoin can be earned with both. Folders use high-end GPUs and CPUs to fold proteins, earning a proportional amount of coins set-aside for their contributions. Miners mine with SHA256 ASICs as usual, securing the blockchain for the Curecoin network. Whether you are heavily-invested in ASIC equipment or still have GPUs and CPUs, you can participate. Due to the nature of folding (diverse, constantly changing, not easily predictable), GPUs and CPUs will both always be relevant, so an investment in consumer hardware isn’t wasted."

FoldingCoin: http://foldingcoin.net/

"FoldingCoin Inc. distributes cryptocurrencies (tokens) to affiliated participants on the Stanford University Folding@home network. The tokens are awarded proportionally according to that participant’s Folding@home credits."

Steem: https://steem.io/

"STEEM is the platform token on Steemit.com. It's distributed to the most valuable contributors by community voting. STEEM is a tradeable token that is easily convertible to Bitcoin and Ethereum."

Einsteinium: https://www.emc2.foundation/

"The defining characteristic of Einsteinium is its ongoing commitment to research and charitable missions. Einsteinium the coin is connected to the Einsteinium Foundation.

Einsteinium coin is a Bitcoin-like currency with a philanthropic objective of funding scientific research, cutting edge IT and crypto currency projects. Our community members vote on which valuable projects the funds will be awarded too."

https://powerledger.io/

"Power Ledger is a blockchain-based peer-to-peer energy trading platform enabling consumers and businesses to sell their surplus solar power to their neighbours without a middleman."