Information on this new tool/service was passed on to me by a good friend of mine. Described on the Icevision website as a 3d virtual reality environment for Autodesk Revit and AutoCAD Architecture, you upload your models to the Icevision where you can walk around the model in real time.
"ICEvision allows you to explore your Revit or AutoCAD 3D models in a separate Dynamically Rendered 3D window.
Through our patented use of 3D video game technology, you're are free to explore your model in a natural manner, simply by walking into your design and taking a look around."
What looks particularly interesting is the iphone plugin!!!
More details can be found on their website..