Obviously i don't claim to know it all and from time to time i run across new tools that many people might have known about but not many have used. I got a chance to use the Autodesk DWF viewer this past week. The viewer allows a user to view, orbit, rotate, walkthrough and make comments on the model at any given time. The beauty of this of course is that they can't directly edit the model, but they can click on buildling components to get exact square footage measurements and updated wall assembly and component information.
The real value we are seeing in this is that we have started including not only our ususal 3d renderings of a proposed building or space, but our BIM DWF file and the DWF viewer as well. The funny part is how involved the owner starts to get in the process and how they feel like they are more a part of the team when they can zoom around this thing.
It doesn't cost a thing to download and even from a marketing effort including the DWF viewer and file is a good way to put your firm ahead of the curve.