The windows 8 consumer preview edition witch can be downloaded and used for free
it's new OS that builds upon the new feature first seen in Microsoft's mobile phone operating system windows phone 7.5.
- click here to download windows 8 consumer preview
you can either upgrade your windows 7 installation or install windows 8 as a separate instance.
for this you'll need to download the consumer preview in the .iso file format and then burn it onto a DVD
installation is quick, you'll at login screen in 10 minutes after restart
they are many new feature in windows 8 and you can also create your own metro style apps through it's SDK and tools
allover it's an full feature loaded new windows
go for it so try it !