Using nothing more than PVC pipe, an Ethernet cable, and a very basic electrical system, [Peter] has built a real MVP of a submarine. No, not Most Valuable Player; Minimum Viable Product.

Building a submarine is hard, and thus it’s a challenge ... The design is straightforward enough, with a PVC tubing frame carrying thrusters for maneuvering, and a central tubular compartment ...

By Choe Sang-Hun Reporting from Seoul North Korea said on Saturday that it was building its first nuclear-powered submarine to enhance its nuclear weapons abilities, and the state news media ...