Note: This does not work on OS X Mountain Lion (10.8.2). It has apparently been fixed in newer versions.
The instructions above are for a Linux machine with Remmina installed, but you can do the same from a tightVNC command line (cli or GUI, Windows or Unix). You can also access using other tools like krdc.
Microsoft Windows has various third party VNC programs available. I have found tightVNC to be the best for my purposes. Also, check out the paid product UltraVNC.