A while back I posted about my 4e players beginning to figure out how to assemble magical circuitry to create magical "machines" that functioned much differently from the magical items created through rituals in 4e. Plants, organs from magical creatures and magical crystals and minerals could be combined to create magical effects. This worked in a fairly straightforward manner; the blast cannons the party made from the legs of genetically-modified partially robotic giant insects and the dark organs of the larval spawn of an elder godcreature are an excellent example.
Next, the party figured out that magical energy could be transformed in the shadow world to enable magical machines to perform many more functions. They first learned about this by observing how shadow pearls in a magical shield constructed by the snake men scientists transformed raw energy and created both a repulsor beam to fly the shield as well as a laser to blast the crap out of things. I want to post more about the magical discoveries the party has made since then, but first I need to lay out some cosmological groundwork.
In my game cosmology there is the physical world, the spirit world and the shadow world. The physical world is a multiverse that I call the IPM (infinite possibility matrix) in my games (I use this cosmology independent of system - I used it for my 3e game and my Mutant Future game as well as the 4e campaign). The main thing distinguishing the IPM from any other multiversal theory is the travel of energy between different possibilities. Imagine every particle of energy in the universe somehow "freezing" in time. The planets and suns and comets stop zooming around and hang motionless, as do the electrons and protons and in turn quarks and neutrinos... and if you zoomed in as far as you could on an individual unit of energy, in the IPM you would discover that the smallest unit of energy both does and does not exist at the same time. In the frozen universe, outside of time, energy flickers in and out of existence. It is travelling outside of time between the different possible universes.
If you could somehow follow the flow of energy outside of time between the different possible universes you would be in the shadow world. The shadow world exists outside of time and the usual constraints on the forms energy can take. It could simultaneously be thought of as an undifferentiated sea of energy, and as a sea of every form that energy could take. If you followed a linear conception of time backward to the big bang, the shadow world is on the other side of the big bang if you kept heading "backward".
The spirit world is the borderland between the physical world and the shadow world. There are as many spirit worlds as there are possible universes, but there is only one shadow world. The spirit world is how/where energy leaves the universe to join the shadow world, and the spirit world is how/where energy returns to the universe from the shadow world. The spirit world could be thought of as a veil that covers the universe and defines its bounds, even as energy flows to and from the universe through the spirit world into deep shadow and all other possible universes. As energy constantly flows between the different probable universes, it is possible for networks of energy to simultaneously become sentient in the spirit world surrounding a universe. Once such a consciousness arises, it persists even though the individual units of energy that make it up are constantly in flux. These are spirits. Different sorts of spirits arise in the different spirit worlds surrounding different possible universes.
Back to magical circuitry - every universe has rules that govern how energy can behave. Anything that breaks those rules is magic. The way that magic functions is to tap into the possible forms of energy in the shadow world and make energy returning to the universe retain these shadow forms. The study of magic is the study of the potential forms of energy, how to tease out the desired form in the shadow world, and how to bring back that form through the spirit world.