OK, here's my first foray into a 3D scene using a SketchUp model I created. Click "Play" below (you'll probably have to install the 3DVia player), then use your arrow keys to walk around. You can zoom in and out with the scroll wheel, look up and down by clicking and dragging the mouse. I don't know if you're supposed to be able to walk through walls, but I was able to (weird feeling!)
The controls on the right side enable you to get a first person (your own) view, or a view looking at yourself from behind. You can also take snapshots of your walk-through.
I've gotten pretty used to using SketchUp scenes to create walk-through tours, but 3DVia scenes are a lot easier to use (or at least they will be when I get the hang of it). This is just fantastic for so many markets: architects and interior designers can show clients their ideas, students can show teachers and classmates what they've come up with. Plus it's really fun.
The dentist office model in the scene above is one I created for Project Spectrum, and you can find it in the 3D Warehouse (click below).
To save it as a 3DVia model, the SketchUp model must be saved as a KMZ file using File / Export. In 3DVia, first upload the model, then create a scene. Once the scene is in your player, you can add 3D models to it, either models you've uploaded yourself, or models other 3DVia users have uploaded.
I'm going to write this up in more detail as a project sometime soon, but give it a try in the meantime.
Anyone can design anything in 3D! http://www.3dvinci.net/