When they open in 2018, the 100-foot-tall orbs -- Amazon calls them Biospheres -- will host more than 300 plant species from around the world, creating what the company sees as the workplace of the future. Amazonians will be able to break from their daily labors to walk amid the greenery along suspension bridges and climb into meeting spaces resembling bird nests perched in mature trees, where the company expects them to brainstorm -- and perhaps even invent the next billion-dollar opportunity.