Generator using Earths's Magnetic field? In the past I've been shown Internet sources claiming a specific generator that uses nothing but the earth's magnetic field to generate power, I'm looking for the name of the generator?
I realize other discussions on this site have claimed (using math etc) that the energy is so minimal it isn't worth the effort, but that's not my question.
I've seen the evidence for the device on the Internet in the past, and I wish to examine the evidence of the device in detail again, yes it's not possible I'm sure by showing me all the equations, but if there are practical implementations of this technique I'd like to take a look.
 A: You can't generate power from a static magnetic field alone.  In this context, the earth is just a permanent magnet, and a rather weak one at that.  To generate electric power from that, you have to move electric conductors, like wires, thru the field in the right direction and with the right orientation of the conductor.
If any electric power is taken from the resulting EMF produced by the moving wire, then a force will be required to continue moving the wire.  Put another way, the wire will "push back" as you try to move it thru the magnetic field.  That push times the velocity represents power you have to put into the system to get the electric power out.  Power isn't coming from the earth.
You can get the same effect by passing a wire thru the field created by any other permanent magnet.  The reason this is usually done instead of using the earth's field is that a deliberate magnet can easily have a much stronger field, although much smaller in size.  You can also get the same effect by holding the wire still and moving the magnet, which is not a option when using the earth's magnetic field.  In the case of moving the magnet, it will require force to move past the wire when electric power is drawn from the wire.
There is no free lunch here, and any claims to the contrary are just bunk and a waste of time to persue.
A: I don't know the name, but you can certainly do it.  Just make a loop of wire and rotate it around a vertical axis.  Use some brushes to allow the rotating loop to make electrical contact with your fixed circuit and take out the energy or spin the circuit with the loop.  You will need some source of mechanical energy to spin the loop-that is where the electrical energy comes from.  The flux you are cutting is about the half Gauss field times the area of the loop.  That will allow you to calculate how much you can generate.
A: generator that uses nothing but the earth's magnetic field to generate power  Set up a coil, or even a conducting disk, and wait for the magnetosphere to billow re solar activity.  You won't get much.  As stated above, spinning a coil or a homopolar generator in 0.4 gauss field won't get you much either.
http://www.lhup.edu/~dsimanek/museum/unwork.htm 
Perpetual motion machines.
