The artist's view of co-creation

Rod has an interesting take on how the co-creation that artists strive for when producing a play or a film relates to enterprise IT projects. I think the same thing is true of products. The best ones are made with users not just for them. The question I have been batting around for the past few weeks is: does co-creation have a place for physical products…you know, real manufactured goods like cars, bicycles, sandwiches and stereo systems? Also, what is the role of openness is the process of co-creation? Is it a necessary or just a desirable condition?
The open source software movement and posts like Rod’s clearly show that both openness and co-creation can be powerful products for IT goods. The example that Rod quotes shows that co-creation (if not necessarily openness) is also a powerful force in the arts.  But will it work for things you can hold in your hand, drive to work and lug home from the store?  I don’t see why not and I’m going to guess that 80% of what we need to make it work has already been well learned by software developers and artists.
Its the last 20% that will be tricky.  Who holds the liability for an “open source” car when its throttle sticks open?  Who can do a recall on an “crowd sourced” MP3 player? What does the financial structure look like for a company with high sunk costs (presses, dies, inventory) and no ownable IP?  Once we get those (and a few other) issues knocked out, the next car you buy may have been co-developed with you and your neighbor and include a complete bill-of-materials in the glove box.