Using ab initio calculations, we analyze electronic structure and vibrational modes of the boron fullerene B(80), a stable, spherical cage similar in shape to the well-known C(60). There exist several isomers, lying close in structure and energy, with total energy difference within approximately 30 meV. We present detailed analysis of their electronic structure and geometry. Calculated radial breathing mode frequency turns out to be 474 cm(-1), which can be a characteristic of B(80) in Raman spectroscopy. Since the B(80) structure is made of interwoven double-ring clusters, we also investigate double-rings with various diameters. We present their structure and HOMO-LUMO dependence on the diameter, and find out that the gap alternates for different sizes and closes its value for infinite double-ring.