BeOS / Zeta
BeOS is an innovatie operating system that is available for a range of different CPU types. The current version Zeta Deluxe 2 has matured enugh to measure itself with Windows.
Zeta is published by YellowTab, more information is available on their website.
Although the packaged version of Zeta already contains a huge number of applications, there is also an enormous offering of freely available software for the operating system.
All PC's by Computer City are also available with the Zeta operating system instead of, or in addition to Windows and/or Linux.