We've been working closely with the world's foremost CAD and visualisation company, Autodesk, to help address this problem for product designers.
The answer is a great bit of software called Autodesk Showcase. Rather than presenting our clients with static, printed out renderings or visuals of what the product might look like (which take forever to produce, and therefore cost the client a lot), we use Showcase to create an immersive, 'live' presentation for our clients.
This great tool means we can, together with our clients, very quickly explore alternative designs, colours, finishes and textures in a 3D environment that reacts immediately to anything asked of it. Needless to say, it's very popular with our clients!