Possibility of using the effects of sleep to induce a virtual environment? I'm not sure what this guy is trying to say, or why his question got closed, but I think I can build upon it and form a solid question. When the brain enters REM Sleep, all sensory input to reality is eliminated or dulled. The person will begin dreaming as the brain creates random impulses and sends them through the brain. Through the techniques of Lucid Dreaming, the subject can learn to control the false dream reality completely. These conditions provide everything necessary for a virtual environment except they are isolated to the individual's brain.

If we were able to induce the physiological conditions of sleep (which should be a simple injection of hormones), and generate these impulses artificially(connecting the brain to a high-end computer program), then we should be able to immerse the person in a virtual environment. Lucidity could be achieved easily by programming the system to leave clues for the subject. The ramifications of this are enormous. For example, a man in China and a man in Russia could go bowling together, without leaving their own homes.

(I'm not sure if this theory already exists, but I definitely reached these conclusions myself.)  

My main questions are: 


What are the hormones necessary to induce sleep in this way?
Is this a safe and reliable way to immerse a subject in a virtual environment?
As a matter of fact, this can be possible in the future. There have been "predictions" that within this century we will be able to upload our consciousness into computers, creating an environment where it will actually be like reality.

Now, off of theoretical, as of now it's impossible to do virtual reality. All I can provide you with is a theoretical answer, which is above.

As for hormones and safety:


Use sleep hormones, melatonin, serotonin


As for safety, it hasn't been done, I can't answer.

http://www.youtube.com/watch?v=tT1vxEpE1aI

That video is an interesting video by Michio Kaku on this topic.