This paper is an attempt to reveal the untapped immense power of the GNU Radio - an open source software, in control and monitoring systems, both real time applications and class-room demonstrations. GNU Radio has already gained wide acceptance and glory in communication and signal processing. As a novel attempt to bring the controlling capability of GNU Radio to limelight, an experiment for temperature control, out of its innumerable applications, and the possibility of a revolution by this free open source software is predicted and explained through this paper. This paper describes the hardware and software requirements for the temperature control experiment with SBHS (Single Board Heater System) using GNU Radio and describes the recommended classroom demonstration.