Our intrepid scapegrace, Mr. Fickens is closer to an answer than he knows. Fact is, the Earth's "spinning" already generates electricity and plenty of it in the core.
The metallic (primarily iron) core in the Earth's center is nearly moon size and spins at a different velocity than the outer shell. Additionally, "... the inner core spins independently but at a slower speed -- one degree a year. At that rate, it would take the solid iron core 360 years to lap the rest of Earth.
The extra rotation apparently comes from a twisting force generated by the interaction between the magnetic fields of the inner and outer cores... The highly conductive iron moving in a magnetic field generates electricity, creating the equivalent of a huge generator, or dynamo, at the planet's center. This electricity, in turn, has its own magnetic field which is responsible for compasses pointing north, northern and southern lights, and other effects at the planet's surface." (Source: The Harvard University Gazette)
Now... if we can just agree on what size and style of plug-in it takes, we'd have all the electricity we could use...