Daniel Nissanoff predicts a $250 billion market in auctioning used household goods.

Americans have over two-grand worth of this, that and the other sitting in spare rooms, overstuffed closets, attics, garages and sheds.

If you’re thinking giant garage sale, think again. What’s true of America’s homes may be true of American businesses in spades. And in Nissanoff’s world, this is where the middleman shows up to sell our stuff – netting us as much as 50 cents on the dollar. Indeed, a crop of startups (eAuction Warehouse, AuctionDrop, I Sold It on Ebay!) are springing up to take care of people who want the money but think online auctions are too much work.

People who were in Silicon Valley, Seattle or San Francisco when the Bubble burst remember locals scavenging for iconic Aeron chairs at parking lot sales. If Daniel Nissanoff is right, the next time you see an Aeron at an unlikely price you can assume it’s either stolen or being sold to make way for a newer model.

But there’s more to it than that. Mr. Nissanoff believes we’re transitioning from a cluttered "accumulation nation" to a culture of temporary ownership in which the movement of durable goods from person to person will be normative — a transition he contends will have an enormous impact on our culture and values.