The underground conveyer.

When you train over a period of time your heart will grow in size, allowing it to pump a larger volume of blood with each stroke (or pump).

Clouds are vehicles for energy. They carry solar energy from the warm tropics to other parts of the globe through weather systems.

One plan is to site such plants in desert regions of north Africa, and to transport the electricity generated to Europe.

Cost: Delivering the same bandwidth wirelessly will always be more expensive, because radio waves - due to the above constraints - require massive amounts of power to work well.