Fermat's Library does annotations for important academic papers. The papers are sent to subscribers at a good cadence - once per week. I enjoy reading them. Not sure if it could ever be a monetizable business, and I doubt the team running it is considering charging.

http://fermatslibrary.com/

I also worked at Reframe It, after you left.

To add to your point, Disqus is also struggling: https://techcrunch.com/2016/12/13/disqus-lays-off-11-as-it-p...

Not to stray too far off topic, but that Disqus story is ridiculous. What do they do that 2 people charging $10/mo couldn't? "Looks like the freemium thing isn't supporting our fancy office, let's try to sell some data out the back door."

I mean, seriously:

But more recently Disqus has been trying out other things to expand its business. That has included a growing programmatic ad platform based around sponsored comments, which debuted in 2014 (it’s this that makes the company money, as Disqus takes a share on ads that run through its otherwise free platform). And earlier this year, Disqus opted for another traffic gain as it relaunched of its own site as a central repository not just of content and comments from sites that you follow and comment on with a Disqus ID; but also of standalone comment threads that existed independent of these, Reddit-style.

This seems like a lot of digging of one's own grave. Apologies if all of this ground was covered in Dec, but it looks like the story never made it to HN.

I wonder if a first use case could focus in on something like https://archive.org/web/, get people hooked somehow, then generalize it to future changes by pointing back at some snapshot maybe.

Personally, I dislike the "get people hooked" formulation.