Nebula, from the Slack team, looks like a really solid solution. All nodes having their own certificate, it doesn't even require to trust the coordination server. I love it!
But I'm surprised I can't find any big company claiming to use it (other than Slack themselves). I can only find 'Home-labbers' and smaller businesses, but no big guys looking into it. At least not publicly. Has anyone seen it deployed in a bigger corporation?
Other than that, I mostly stopped using it because it forces you to regularly rotate all certificates, and for my personal purposes it was too much of a hassle.
I still like the project a lot and wish it would be more prominent. Nowadays everyone immediately seems to recommend Tailscale.
I'm planning to replace the traditional network architecture in my homelab with it to practice Zero Trust.