It's not every day that you come across a company like this. You really have to give it to YC for supporting some of the most ambitious ideas that are not even within its wheelhouse. It's one thing to back an early quantum computing company like Rigetti - I would imagine that Sam Altman and other partners at the time knew a thing or two about that field. But a DAC plant? How do you fact check that in a 10 minute interview?

Another notable YC investment that I always admired was Immunity Project (an attempt to make a free HIV vaccine) - https://www.ycombinator.com/companies/immunity-project.