Can someone help me think of 100 future technologies/inventions?

[Storm_Of_Snow]

19) Transcontinental super-trains connecting every continent on the planet, except for Australia (South America - North America - Asia - Europe - Africa). The trains are only for freight, plus few very privileged people -- the threat of terrorist attack is too great to allow for regular passenger service. Cargo is extensively screened.

Any particular reason not to extend it to Australia? If you're thinking land connectivity, you can go down through Malaysia, turn east into Sumatra, Java, Timor, island hop into Papua and then go south across the Torres strait.

Conversely, to do Europe-North America, you're either going across the Bering Strait from Russia into Alaska, or tunnelling hundreds of miles of rock under the Atlantic for each leg to go Norway-Faroe Islands-Iceland-Greenland-Canada.

Anyway, my choices:
42) Faster than the trains mentioned above, especially for really long-haul - space planes, as per the Skylon concept (https://en.wikipedia.org/wiki/Skylon_(spacecraft)).

43) Hydrogen fuel cells replacing internal combustion engines, plus changing petrol filling stations to Hydrogen.

44) Cybernetics.