Jeffrey Wegesin is a furniture maker. His most popular creation is a curvaceous side table, and even though he has sold only two copies of it, he has already turned a profit. He did it without so much as setting foot in a wood shop. And he is not alone. Wegesin is one of 5,000 merchants who have established accounts with Ponoko, a year-old on-demand manufacturing service in New Zealand.

Welcome to the age of the instapreneur. With nothing more than a design, amateurs can manufacture jewelry, robots, T-shirts, furniture — anything. No warehouses. No minimum orders. And no money down.

Thousands are launching instant businesses.

On-demand manufacturing could eliminate that constraint, leading to a world where products are always available, nothing ever gets discontinued, and the virtual shelves are always stocked.