100% urbit. The idea behind it (briefly: "personal server", an easy-to-use, no-frills place for an end-user to run server-side use cases like storing important files, hosting a blog, etc that's portable between cloud hosts and designed for long-term stability over performance) is a good one. Implementing it as a novel VM with built-in identity and crypto makes sense. It includes some genuinely hard/useful features, like exactly-once messaging between nodes. Kelvin versioning (counting down towards "done" rather than counting up as features are added) is a great idea for software that serves infrastructural purposes. Charging a one-time fee for cryptographic identities is an elegant way to make a de facto reputation network that disincentivizes malicious actors, and is also that rarest of beasts, a non-dumb reason to use a distributed ledger.

It had so much going for it, but it was DOA from launch for two reasons: first, the implementation is so bizarre that the kernel documentation is frequently mistaken for an elaborate joke, and second the founder's racist blog went viral at virtually the same time as the public launch. It's not technically failed I guess as it's still being developed and does work, but a network without a network effect can only go so far.

I honestly think the "personal server" idea would be incredibly useful, and it would also be very profitable (not the software itself, but for cloud providers) if every suburban family rented a $15/mo VPS. I post about it here from time to time in the hopes that someone will fork it or re-implement what is basically a great idea, but in a non-ridiculous way and without #cancelled taint of the founder. Bezos, if you're reading this, please put a small team on it just to see if it goes somewhere, I'll be your first customer.