Wanting to experiment with node.js, I made a simple pseudo-chat application.
How it Works
As a user types, letters are added to the database and then added transmitted to everyone currently connected to the server. The response is almost immediate and fast enough to support typing into the screen. With multiple users, the letters between one user and another might get intermixed but are identified by the user’s color (assigned through the users’s IP address when they connect to app).
A node server with a mysql database and socket.io for websockets. I also use express for serving the index.html