khush792001 -
Even though this is almost 18 months too late, maybe it will spark some other discussion about grids and using idle PCs.
Your analogy of shifting processing cycles aselectricity flowing is flawed since processing power must be used at the point of creation. I can't cram any more cycles into a CPU than can be executed by the processor.
The idea of harnessing idle processors has been around for several years. There are many different systems for doing such things, but each involves exporting instructions and data to the external processor for execution. This can be as tightly coupled as creating a virtual cluster of desktop PCs or loosely coupled by sending complete jobs to processors and waiting for a result before sending another task.
One of the big problems with such wide-area distributed computing is the data being moved around. For LAN situations, the data may be located on some shared file server. For cases where you wish to harness processing power in different parts of the country, the problems that require such large-scale computing resources will likely have large-scale (100's of terabytes) data requirements. Thus, a more interesting problem would be how to schedule distributed computations in a network of PCs would be assigning tasks that involve the minimum amount of data movement. That could be a potentially valuable research project.
-- clay