[Question] What EA projects could grow to become megaprojects, eventually spending $100m per year?

Ben Todd (CEO of 80,000 Hours) says “Effective altruism needs more ‘megaprojects’. Most projects in the community are designed to use up to ~$10m per year effectively, but the increasing funding overhang means we need more projects that could deploy ~$100m per year.”
https://​​twitter.com/​​ben_j_todd/​​status/​​1423318852801290248

What are some $100m projects that you think might be worth consideration?

By megaproject, I’m referring to any project that could eventually be scaled up to $100 million, not ones that are planned from the start to cost $100 million. In many cases, this could include very small efforts that would have to achieve multiple levels of success to eventually get $100Million+ per year.