Here are my thoughts

1) Free p2p money transfers / gateway to bitcoin or other crypto-currency so that it's more widely adopted

2) Better open bank accounts - allowing open transparent accounting for organizations and companies

3) Solve democracy - better analytical tools for mass discussion, arguments and decision making which will encourage use of facts and science, and discourage politics

4) Human-Machine interfaces - memory augmentation

5) Solve the common cold and influenza

6) Robotics - better batteries, finer motors and sensors - possibly through the usage of biological systems

7) Public access to satellites - realtime security monitoring, crops analytics and forecasting

8) Solve weather or create private air-conditioned jackets ;)