Interactive Interior Renderings?

[Steve M]

Trying nXt after using AccuRender and loving it so far.

I am working on an interior model and want to produce an interactive rendering.  Ideally a 3D PDF that the user can walk through and look around.  This technology doesn't seem to exist yet for interior renderings.  Are the old spherical panoramas still the best bet for interiors or is there a new technology that will allow users to move walkabout style as well as just look around?

To clarify, I am something interactive as opposed to an animated walk-through that the users can't control.

Thanks!