@hexxeh put together a 1gb USB flash drive image of Chrome OS. You can find out more about it here: http://carbon.hexxeh.net/chromiumos

The catch is it's a raw disk image intended to be written to, and booted from,  a flash drive... making it a little tricky to use in VirtualBox as it doesn't support booting from USB drives. So here's a VirtualBox disk image of hexxeh's Chrome Os Diet... just download, unzip (well, "unrar" technically) and start it up :)

Thanks for your work hexxeh!

(The default username and password are both "facepunch" - speaking of which, check out http://www.facepunch.com which I believe hexxeh is involved with)

My download mirror: ChromeOS-Diet.tar.gz (290mb)

Download the VirtualBox image here: ChromiumOSvdi.rar (290mb - extracts to 800mb)