This is a Link to a page where you can download the ChromiumOS Build ready to be written to a USB Drive and booted from.
I am aware the download link on the page is a torrent before anyone who checks this out reports this discussion for linking to torrents which is now against the rules, but i have spoken to Simon about this privately and gained his permission to do so.

http://carbon.hexxeh.net/chromiumos/

I'll agree to this, As long as Simon's cleared it i'm cool with it. As a matter of fact i've been looking for a download of this been wanting to try it. Announced :)

For anyone who has been interested in this, the latest builds on hexxehs site now fit on a 1gb pen drive with a capacity greater than 950mb, unless otherwise stated and feature better wifi support.
Anyone looking for resolutions bigger than the 800x600 given is out of luck though as no other resolutions have been worked into chrome os YET!

how do you install it ? on a seperate partition?

I presume so, unless it's automated, in which you should use a separate Hard Disk.

Google Chrome OS - First Impressions

Hexxeh has now released his latest Chrome OS build: Flow.
Flow offers even more hardware support, an auto-updater, webcam support and an improved application menu & directory. The only drawback with this is that Flow will NOT install onto a 1gb penstick like the previous version did, it will require a 2gb or larger usb pendrive.
Visit his site for download links and help on how to get started and installed.
http://chromeos.hexxeh.net/
http://chromeos.hexxeh.net/wiki/ ( Hexxeh Build wiki )