The document discusses several proposals for underground and high-speed transportation networks: - Elon Musk's plan for The Boring Company to dig tunnels under LA to alleviate traffic and eventually have a 30-layer underground network for cars and a Hyperloop. - The Hyperloop concept of pods traveling in vacuum tubes at up to 800 mph requiring little energy due to little air resistance. - Hyperloop One's control systems aim to keep everything on the main Hyperloop line moving at optimal speeds and calibrate pod entry to prevent congestion and maximize efficiency. - The proposed "Interstate Skyway" system of tubes suspended in the air to move passengers and freight above ground level and eliminate traffic.