As far as I can tell, the basic idea behind meditation is to be focused on the present moment. Most people on this planet, myself included, are usually in three places at once--past, present, and future. We spend most of our conscious thinking remembering or projecting, and miss the now. Apparently, this is a very scary idea for a lot of people. It's a direct threat to the ego, which loves to be right about things. When I meditate, I get to the place where there is nothing lacking at this moment. It doesn't last long, though. In that place, the ego is temporarily disabled, and I'm back in the river, moving with the current.
The first book that gave me a glimpse into this state was by the now late Jimmy Sloman, called Nothing. He did so much work in this area, and was also a trader. There was a tape I used to listen to called, "An Evening With Jimmy Sloman." It detailed his first experiences with trading, and how he was able to acquire a large sum of money through visualization. Don't know if it's still available, but I'd like to own a copy. I was able to work with him briefly at a seminar many years ago, and it was great.