The Opus Office Tower – a 21 story office building with a void at its center (supply your own metaphor) due for completion in Dubai by 2016, designed by Zaha-Hadid architects, what sez:

The Opus comprises two structures, conceived as a single cube eroded by a free-form void, which appears to ‘hover’ above ground-level. A pixilated reflective façade renders the cube full by day; by night, it ‘dematerializes’ as light floods the void.

mymodernmet/designboom