PubNub and Tessel are collaborating to host a Hack Day on October 25, showcasing the capabilities of Tessel, a microcontroller that runs JavaScript and is equipped with a built-in WiFi chip, enabling it to run internet-enabled programs independently. Tessel's integration with PubNub enhances its functionality by allowing it to publish and process data in real-time, such as environmental metrics from modules like climate, accelerometer, and RFID. A simple example demonstrates how a Tessel can blink an LED in response to messages received via the PubNub network, illustrating the ease of connecting multiple smart devices. The setup process for deploying code to Tessel is straightforward, and users can explore additional resources and examples available on a GitHub repository. This collaboration emphasizes the seamless communication between devices and the Internet of Things, facilitated by PubNub's extensive real-time network capabilities.