Discussion Title: Best futuristic technology to bring mainstream?

1. Best futuristic technology to bring mainstream?
1.1. Solar cars
1.2. Cold fusion
1.3. electronic paper
1.4. See-through electronic screens \(like TVs, phones, etc.\)
1.4.1. Con: People may run into it
1.5. Universal USB
1.6. solar panel spray paint
1.7. Lagrange colonies
1.8. Orbital rings
1.9. Medical pod
1.10. The working time machine
1.11. Nanobots
1.11.1. Pro: These could help extend people's lifespans.
1.12. A teleporter
1.13. Hoverboard skateboard
1.14. Flying cars