Hundreds of millions is in order of percent of the human brain, so if that matters, it is needed to make an image of the data. This can be carried out using a well-known method, which is (brain) mapping. Having said that, the method visualizes the most dominant data in a neuromorphic architecture.
I would suggest the following resource and think about the difference between representation and presentation. Think about what is useful to present in context to real problems or missions, not generally. Dr. Inselberg‘s book on parallel coordinates and multi-dimensionla visualization is a great resource. He received accolades from Stephen Hawking as well.