Back in 1968, Charles and Ray Eames created an amazing short film titled "Powers of Ten" to illustrate the size of our universe from the very largest to the very smallest scales. If you've never seen the film below, you can watch it here:
The reason this comes up is because of an amazing interactive tool from Cary Huang that simulates that experience called The Scale of the Universe 2. If you haven't checked it out yet, we strongly encourage you to pull up their site and play with it.
Another great way to experience the Powers of Ten, as Frank mentioned in his previous post back in 2008, is with the excellent KMZ file
that Richard Treves posted on his Google Earth Design blog. It's only a subset of the area shown in the movie, since Google Earth can't zoom in or out nearly that far, but it's a neat way to see it for yourself!
Not only can you experience part of the "Powers of Ten" in Google Earth, but the film was part of the inspiration for the original Keyhole project that later became Google Earth!