a robot-only captcha.<p>or a party in a box.<p>or huge nixie tubes based on el-wire.<p>or a shoe installer. Stick your feet out one by one, and it will put on a shoe each time. (perfect for next to the front door)
Ethics in political decisions.
A Pill for the ultra greedy rich people. When they take it, then their greedyness, will get cured. Same for empathie to other humans, animals, nature itself.
The rest of world problems, should be fixed then with these 3 solutions :)