Regardless of whether you call the inflatable edifice pictured below a bubble building, hemisphere house or pumped-up pleasure palace, we're sure you'll agree it's the most revolutionary concept in mobile living since somebody invented the trailer--and a lot more fun. Created by a Los Angeles design group named Chrysalis, the polyvinyl Pneudome, when collapsed, fits into a 42"x60"x12" box. To turn on the bubble-house machine, simply spread the dome out on a flat surface, fill the base ring with water (optional cable anchorings also available), then attach the portable air blower to an external port--and up she rises. In about eight minutes, you have nearly 500 square feet of living space to do with as your imagination dictates. And, to make sure your air castle doesn't crumble, you keep the blower going; a gentle current of air not only ensures that the pad remains inflated but ventilated and dust-free, too. Although opaque models are also available, we prefer the transparent number, shown here. The price for a Pneudome that's 25 feet in diameter and ready to rise is about $1950 including blower--a sum that surely won't blow your bank account. For more information, write to Playboy Reader Service, 919 N. Michigan Avenue, Chicago, Illinois 60611.