Free Operating System And How To Try It Out

BeOS was one of those promising operating systems that never really managed to gain any kind of market share. The Haiku project has taken it upon themselves to continue the development of BeOS, and has slowly been making their way to a version 1.0 release.
Haiku is a new open-source operating system that specifically targets personal computing. Inspired by the BeOS, Haiku is fast, simple to use, easy to learn and yet very powerful.
http://haiku-os.org/

You can try it out in a 'Virtual Machine' on your desk top if you are not timid and can follow simple instructions.

10 steps to getting a Haiku VM running.

Read more:
 http://www.brighthub.com/hubfolio/matthew-casperson/blog/archive/2011/08/09/8-steps-to-getting-a-haiku-vm-running.aspx#ixzz1X5epwHwd