Voyant Server is a web application launcher for Voyant Tools – it makes it easy to run a stand-alone instance of Voyant Tools on your local machine, which has several potential advantages (performance, security, privacy, reliability, etc.) compared to the hosted version.
See the latest release and download the VoyantServer zip file. Unzip the file (be sure to actually extract the contents into a real directory) and double-click on the VoyantServer.jar file (on Macs you may need to Ctrl-click on the VoyantServer.jar, select open and confirm the opening – this is because of security precautions in OS X).
Once you open VoyantServer.jar a controller application will appear (that allows you stop stop the server, see error messages, change settings, etc.) and a new browser will also appear with Voyant Tools. That's it!
Voyant Server is released under the same license as JettyDesktop, the GNU General Public License v3.0 (see license-GPL3.txt in this directory).