The New York Times had an article recently about Google's experimental operating system that is built around their Chrome browser, with a link to Hexxeh's Flow build designed to boot from a USB drive.
Since I had looked at the OS earlier, I thought it would be interesting (and probably safe) to try it on my laptop, and in a few minutes I was able to download a compressed image of the OS, install the code needed to decompress and de-tar the file, install the code needed to put the image onto a USB stick and then get all that running and the image on my USB stick.
Unfortunately my Sony VAIO X-series machine didn't just boot from the USB port and a quick search on the Web seemed to show that VAIO's won't do that. Fortunately my son was in town and helped me get into the BIOS and change the setting so that now my machine checks the USB ports -- success!
So, the Chromium OS came up, I was able to log in, get on my local wireless network and start browsing the Web. Unfortunately the system was so slow as to be almost unusable (several seconds for simple operations such as highlighting a link) on my machine. The FAQ implies the slowness is due to limited hardware support in the OS, so others may have a different experience.
The good news is that it did work and trying it out didn't seem to hurt my machine, but until something speeds up, it is not even fast enough for me to play with yet.
I still think the idea of an OS focused on Web access is an interesting idea.