Chrome has recently been open sourced by Google as a developer preview. Its very young, clearly has some issues and needs serious work, however it is usable and lots of people have managed to get it running in a virtual machine or via a USB key.
Chrome OS is clearly based on Ubuntu(if you press Ctrl+Alt+T to open the terminal, you can see the Ubuntu Karmic development branch message) meaning hardware support should be excellent. However, its been heavily stripped down
For most people, Wifi doesn't work. Without Wifi, Chrome OS is pretty useless as it relies heavily on "the cloud" for most of its features.
My laptop uses the Intel 5100 wireless chipset, and I was dismayed that the wireless didn't work out of the box, as every Linux distribution has supplied drivers with ease. Installing the firmware seemed like it might be difficult at first, as the root file system is read only. However, getting it working only took two seconds, and if Wireless works out of the box for you in Ubuntu Karmic, it'll also work in Chrome OS.
Note: Your primary hard drive will need to have Ubuntu Karmic on it for this to work
Login using the default details (username: chronos | password: password)
Open a terminal with Ctrl+Alt+T - you should be logged in automatically, if you aren't use chronos and password again to login.
Remount the root partition with read and write permissions (when prompted for the password, use password)
sudo mount -o remount,rw /
Mount your primary hard drive, which must have Ubuntu Karmic installed!
mkdir /tmp/disk && sudo mount -t ext4 /dev/sda1 /tmp/disk
Browse to the directory that contains all the wireless firmware
At this stage, if you know the firmware your laptop uses, you can copy the firmware applicable to /lib/firmware on your Chrome OS USB Key. If you're not sure which one your laptop uses, simply copy them all - this'll slow down boot up times a little bit however
sudo cp -r * /lib/firmware
Reboot! Your Wireless card should now work, however you may need to press your wireless activation button
Obviously this only works for the easier wireless drivers that are supported out of the box on Ubuntu. However, once you have read write access to the root partition, you can do pretty much whatever you like, including installing more difficult wireless drivers using apt-get or ndiswrapper. You'll need to add the karmic repository to /etc/apt/sources.list first however.