BackTime is All You Need

The only truly finite resource and thus the most valuable one. All other resources can be derived.

The young trade time and energy for money and knowledge.
The old trade money and knowledge to save (but not gain) time.

So it is said that the young are rich in time, though this fortune may be easily squandered.

Probably, the noblest thing you can do is dedicate yourself to save people time. Think of how much time has been saved by faster transportation methods. How many more hours people are now able to be spend with people they love, doing things they love instead of in transit.