The Matrix has taught us that every human is essentially a old-fashion light-bulb. 

How much heat, on average, does the entire human population dissipates per second? 

Is this sufficient to be accountable for global warming?  

This is as naive as it could possibly be.

If you look at the equation of Beta Decay, in Nuclear Physics, you notice that there are a lot of electrons going out.

Can you force these electrons into a wire somehow, and use them as electrical energy?

Because of their charge, are positrons any good as a candidate for antimatter storage systems?

Imagine if you could pair produce, then inject the produced electrons back into the grid and store the positrons for later use. All that in a process that is economical advantageous. Oh, that would be neat. 

What if we created a large-scale version of a copper wire, just for fun? It could be used in science classes.

There would be spheres, with an condutor core and insulant cover. These spheres would be charged, for example by a Van der Graaf generator. 

The spheres would float in water streams, driven by pumps. 

As the spheres flow, does the water or pipes get warmer, such as in an analogous to a electrical resistance?

If you make a coiled pipe, would there be a magnetic field if the stream circulated it?

Now imagine that you place two spheres on an axis, and this axis can rotate freely by its middle point. Place a circular stream around it, with a pump, and put some "electrons". Does the bipole rotate?

What are physical constants?

If you multiply all physical constants to each other, and multiplies to x, and finally equates this to 1, how much is x? Is x the value of all the constants we don't know yet?

Can you arrange all the physical constants in one equation, using dimensional quantities? Are we still missing constants? Can you tell? Can knowing what is left hint about what this quantity is about?

There are materials, such as Invar, that hardly expand due to temperature variations. 

Produce two really, really smooth slabs of Invar. Place them side by side, with a small gap in between them. Now heat one slowly in a very controlled manner. You should have a really tiny gap now, that you can control.

Can you use such a gap to separate gases, by atomic size?

How so? let me elaborate some more.

If you have a gas with three types of atoms, of diameters A, B and C. The sizes relate to each other so that A > B > C. C has the smalest diameter. 

Make an opening of a size intermediary to B and C. Pass the gas on the aperture. Only C will get through, because A and B are larger than the size of the opening. You've separated C. 

Now make another opening of size intermediary to A and B. Pass the gas that contains A and B together. Now, only B passes. That is it: you've separated the gases A, B and C.  

Sometimes we use a metal to protect other from corrosion because it is more easily "eaten" away. 

Could we regenerate this metal using electricity, so we don't need to replace the sacrificial anode?

Maybe this is already done.