I would say (profitable) fusion power (other than the Sun's...), but that may be 20 or 2,000 or 2,000,000 years from now so... I'll go with mind-controlling ma

I would say (profitable) fusion power (other than the Sun's...), but that may be 20 or 2,000 or 2,000,000 years from now so... I'll go with mind-controlling machines. I know the US military is already quite advanced in that regard (trained pilots can control helicopters, jets too iirc), we've all seen the monkey using a third mechanical arm after a few minutes of training, there's this game with the ball in a magnetic field... mind-controlling stuff is going to be immensely powerful. And so swell. The human-machine interface (how fast we can transfer information into the machine, how fast we can intake what it outputs) is the weakest link in the chain. Improve that, and you massively improve our capabilities, our power to do "everything else". Imho. And it would be so cool to feel like Jedis or Q's hehe. And robotics, a "smart"-world IoT-enabled at every corner, and you get an idea of a totally surreal world for us.