Thorium Reactor
The so called "Canadian" CANDU Reactors can use yellow cake (natural uranium), thorium, old "spent" fuel rods from light water reactors (the ones that have to be kept in cooling ponds that blew up so nicely at Fukushima, can be refueled on the go, can use weapons grade uranium, etc....really the most versatile and safest reactors out there. This is a bit of "old news" really....