JRemoteforMyth is a small Java application ge that will let you control your MythTV box directly from your desktop.
JRemoteforMyth is a very small application, simply displaying a button pad for pushing 'keys' on the remote. Click on the image for a larger version.

JRemoteforMyth may be launched several ways. If your browser has JNLP enabled, simply click here:
If your browser does not launch this file correctly (for instance, just shows the XML in a screen), try launching via the command line:
javaws http://www.stonekeep.com/JRemoteforMyth.jnlp
As new versions become available, WebStart will automatically download the latest version when you start. Enjoy!