What follows is an explanation of the cause of paranormal powers coming about in my campaign world. The direct cause of powers is an enormous "virtual machine" which extends over the entire solar system but is invisible and massless, which I call simply the Machine. The Machine is a result of a hundred thousand years or so of technological development in a parallel universe, but due to catastrophic events in that world it is currently nearly uncontrolled.
Approximately 370,000 years ago, a natural event took place where our universe/timeline split up into two parallel universes, which at the point of splitting were identical. Due to the vagaries of dimensional topology, time passed at a different rate in the parallel universe, hereafter called simply Otherworld.
Again due to natural causes, the passage of time in Otherworld did not remain in synch with Earth. The time rate rate gradually drifted until it was 9.4 times the rate of ours (i.e. each year on Earth is 9.4 years in Otherworld). Thus, on Otherworld, humanity reached technological transcendence while Earth civilization was still in its infancy. The Otherworlders learned how to manipulate basic forces, and even manipulate N-space itself. They could create "virtual machines", which were dimensional constructs which were invisible and massless, but could be controlled to produce nearly unlimited effects.
Obviously, coordinating the whims of transcendent beings is an enormous task. With the power to do whatever they wanted, there was inevitable conflict. Virtual machines would interfere and crash, or global operations would conflict. One person's manipulation of Phobos might interfere with another's changing the Martian landscape, say. As more and more machines were built, eventually they decided to centralize.
The Machine was built -- a single virtual machine of near unlimited power which spanned the entire solar system. To control it, various sides agreed upon the Keystone: an artificial intelligence which would be responsible for coordinating, organizing, and distributing the resources of the Machine.
In short, the Keystone worked. It was intelligent and diplomatic, resolving conflicts and solving problems over the fair distribution of power.
Each person was given an artificial "soul" -- a virtual machine which shadowed them and recorded every change that happened to them, so that if they ever died they could be revived in exactly the state that they were left. The Keystone's foremost command was to safeguard the lives, minds, and freedom of all people.
Now into this picture steps a visionary named Ayjiem - an idealist who had his own idea about what humanity could become. He was a revoltionary trapped in a world where revolution was impossible. Nothing could take over as long as everyone had power as distributed by the Keystone.
However, Ayjiem researched. He discovered a parallel universe very close to his own, with a parallel Earth and human civilization. Thus he worked for a long time devising his takeover.
He created robust tools which had no dependence on the Machine: low-tech items which were purely physical like ships and guns. He manipulated people he convinced, shaping them into willing, independent tools. Finally, he created a program to overlay upon his own mind, so that he could single-mindedly pursue his goal over millions of years, if neccessary.
You see, he had built a weapon which would knock the Keystone out of the Machine, sending it across the dimensional gap into Earth. Before it recovered, he would seal it off from control. Utter chaos would follow, raining havoc and killing millions of people.
However, people's virtuals "souls" would remain intact. They were designed to be independent of any problem with the central system. As Ayjiem reasoned, he could build a new, better world within about 13 million years. Once it was complete, he would simply "reboot" everyone to the state just prior to his takeover.
As it turns out, Ayjiem's plan worked. On Earth, in the year of Our Lord 634, October the 9th, a strange object appeared on Earth. The Keystone had been knocked into a parallel dimension, where suddenly it was trapped in a moral dilemma. Finding a world of unprotected humans, its first duty was to provide each of them with a virtual "soul" which could not interfere with their lives. The only leeway which it had was in children conceived at that time, whose lives it could alter. During the milliseconds it took for the Keystone to do this, Ayjiem's trap fell, sealing the Keystone upon itself.
None of the Earth noticed this at the time, but later, a select group of people found themselves immortal, with a strange sense of mystic forces around them, and an overwhelming urge to wander the globe.
On Otherworld, centuries passed in agony. Waves of new horrors passed over the population after the initial holocaust. Ayjiem slowly tried to take over the broken parts of the Machine piece by piece. Recall that each year on Earth is 9.4 years on Otherworld, thus much was altered there.
On Earth, another secret event occurred in the year 1898. An unnamed immortal found the Keystone as he had literally been born to do. It was in storage in a museum in England, where it had been brought back from Africa by an enterprising geologist. Acting by instinct, he stole the stone and brought it home. Over the next few days, his presence aided it in breaking the outer seals constraining it. Before he could complete the task, however, the immortal was captured by a crimelord who was interested in his theft.
The Keystone took all this in stride. It was blind, and had no direct control over the Machine. What it could do, however, was authorize use of certain of the Machine's functions to certain people (that being its job, after all).
Thus, it decided to maximize its chances of being released. It would provide power to a particular type of person, who would most likely take an active hand in the strange occurences around them. These people were mature, intelligent, curious, and aggressive.
To maximize the diversity of their efforts, each person's power was unique, and the effectiveness of the powers was distributed equally. It had no idea of the situation they were facing, what their knowledge or ideologies were, or even if they would use the powers.
To do this required an enormous period of time: stretching out and contacting the Machine in Otherworld, and extending its field to cover operations on Earth despite the havoc wreaked upon it by Ayjiem's millenia of work.
Thus it was not until 1923 that the first paranormal powers were demonstrated publically. It was in that year that a man by the name of Philip Williams wwas arrested for a mysterious bank robbery. A policeman observed keys floating towards the cell and raised the alarm. In the ensuing confusion, Philip was recaptured, but he disappeared from prison some two months later.
Since that time, a wide variety of types have gained powers and used them to gain influence, power, and advance causes - but most of all to figure out more about who and what they are.
After almost 13 thousand years of Ayjiem's conquest, the face of Otherworld is much changed from what is used to be. Here I try to summarize the state of what remains of the virtual machines.
There are also a variety of non-virtual machines: artifacts from Otherworld.