Ulteo http://www.ulteo.com/home/en/virtualdesktop?autolang=en today unveiled their Virtual Desktop which is a free, full Linux desktop that runs seamlessly on Windows. It's not running under Xen or VMWare, but instead uses the coLinux patch, which they claim allows the system to achieve 'great performance, close to a native installation on the PC.' No need to reboot the system anymore to switch from Windows to Linux.
I will still prefer http://www.andlinux.org/ for when I need to fire up a quick linux system, its more stable and based on Ubuntu http://www.ubuntu.com/ they both use the same coLinux patch.Finally, the stability and security of Windows with the application availability of Linux… but really I wonder if I can get WINE http://www.winehq.org/ running under coLinux. Firefox now works great in Wine, so I can run Firefox in Wine, on Linux, on Windows, and maybe just maybe I could run that copy of windows on parallels http://www.parallels.com/en/products/desktop/ on my Mac.