I believe they exist. It just shows the awesomeness of God and the ways he can communicate with his people.  I do not; however, believe we can use these to predict the future, or get any secret meaning, at least not yet.  There are too many possibilities and we are not smart enough to completely figure out the code to be able understand the true meanings of what we are seeing. As with all things, when God wants us to understand it we will, and not a second before.  That doesn’t mean we can’t look though. The people of the early church couldn’t understand Daniel or Revelation as we can today.  All will be revealed in the next thousand years.  After the first 1000 years, we will only begin to touch the vastness of the intelligence of our Lord and Savior, it will be an awesome time and the codes will seem like kindergarten stuff.