There are several open source packages for X11 available for Windows. In the Spring of 2011, COS 333 had students use Xming.
From Apple's Knowledge Base HT5293
X11 is not included with Mountain Lion, but X11 server and client libraries for OS X Mountain Lion are available from the XQuartz project: http://xquartz.macosforge.org. You should use XQuartz version 2.7.2 or later.
The native windowing system on Linux is X11. If you are already running a graphical desktop, X11 is already installed.
PC X Server Software and X11
To use the X Window System, you must have an X Window System Server installed on your computer. A program named Xming is a free X Window System Server for Microsoft Windows. Follow these instructions to download Xming. Using a web browser:
1. Visit the web site "http://sourceforge.net/projects/xming.
2. Click on the "View all files" button.
3. In the resulting web page, click on the "Xming" item, and then the "18.104.22.168" item to reveal the "Xming-6-9-0-31-setup.exe" link. Click on that link to download the file to your local computer.
4. In the same web page, click on the "Xming-fonts" item, and then the "22.214.171.124" item to reveal the "Xming-fonts-7-5-0-25-setup.exe" anchor. Click on that anchor to download the file to your local computer.
Follow these instructions to install Xming:
1. Execute the "Xming-6-9-0-31-setup.exe" program on your local computer to install Xming. Use the default install settings.
2. Execute the "Xming-fonts-7-5-0-25-setup.exe" program on your local computer to install Xming fonts. Use the default install settings. Follow these instructions to use Xming:
1. From your computer's Start menu, choose "All Programs | Xming | Xming" to launch Xming.
2. Launch PuTTY (or some other terminal emulation program).
3. Change PuTTY settings as usual ("Window | Colours | Use system colours"). Then change one more setting: make sure the "Connection | SSH | X11 | X11 Forwarding | Enable X11 forwarding" check box is checked.
4. Use PuTTY to login to cycles as usual. Any graphical application that you launch on cycles will display its windows on your computer.