Novel Looking Speakers

Saw this speaker that should be perfect for those like me who have to place their set in their bedroom,

http://www.everything-but-the-box.com

Hears that it has a 4 inch morel mid-range and a SEAS 27mm tweeter. Looks like an open baffle in concept except that aluminium spherical enclosure. No idea on how this works or what that spherical enclosure does to the sound but looks quite impossible to DIY one on similar lines.