This .bat script launches a ArcGIS Desktop app using the specified license level. The script assumes that the desktop is set up for concurrent use, not single use licensing.
To use the script, edit and save the code to a text file and rename with a .bat extension. Users can run the .bat file with a double-click from Windows Explorer (it will then start up the app with default settings), or you could setup a shortcut that provides the command line arguments as they need.
The nice thing about this script is it does not require the user to alter any global environment variables or run anything that requires elevated privileges.