Filecoin.
I have seen the website, whitepapers, and different videos.. from promos to some guy giving a talk.
But the only access you get to actually use it is a waiting list, unless you consider some of the underlying IPFS technology it uses that you can get from other sources (which is a different beast entirely).
It's likely I'm not meeting some prequalification requirement for the access, but this unfortunately means I can't get excited. If I can't test it anywhere and have never made it run myself, I have to withhold judgement.
IPFS itself is supporting evidence - it shows that those people can create a working and actually useful product. Filecoin seems like a good fit for the "incentive layer" above IPFS, and from what I remember from the ICO, they did their best to make it legally in the clean.
I guess we'll see what happens when (or if) Filecoins get released.
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