For when you get tired of having to open the command line to quickly check a javascript demo that requires the code to run over a server.
Save the file server.command on your machine, make it executable chmod u+x server.command, drop (with copy) the file in the demo folder, double click on it. Press the reload button on the browser window that automatically opened.
For the nodeserver, you must have http-server pre-installed (npm install -g http-server)