Body theft could become a reality if mind-transferring technology becomes available. If we are more than our collective thoughts, and inside our bodies there is some form of spirit or essence, then it may be possible to inhabit another person's body or potentially upload yourself into a completely digital world.
Of course, we don't know what it will mean to upload or transfer a mind from one body to another. Yet, with the mega blockbuster film Avatar exploring this concept heavily, is it not also a possibility that this technology (in either spiritual or technological form) may be used for evil?
Before we dive into the future implications of mind body transfers, a realm science and technology is about to enter, it is important to understand that these are actually ancient concepts. There's another field which has already contemplated the idea of mind-transferring for many centuries, this has been the spiritual systems.
The spiritual technology not only serves to help rid someone of an unwanted guest, but also to download knowledge from higher or alternative planes of existence. Whether this is true or not, it may not be fully understood or formally "discovered" by science until a later date. What I do propose is that, as we gain a better understanding of what consciousness is and its capability to shift in and out of the body, people or entities may use this technology to effectively steal our physical bodies. Why abduct a person if all you want is located in their minds? This may work in reverse as well, as our bodies could be stolen to transfer our consciousness out and replace it with the consciousness of another person on the brink of death.
Artificial intelligence is just such an entity that could work its way into the minds of people and effectively possess their bodies for the purpose of its own knowing. Of course, much work in brain computer interfaces will have to be undertaken before this is possible, yet we must never forget that our bodies are a material possession, therefore temporary and never fully ours to own.