A chaotic pendulum made with magnets and fishing line demonstrates the principles of non-linear dynamics and chaos theory. When the pendulum, consisting of a magnet, swings over a base with fixed magnets, it experiences complex, unpredictable motion due to the variable magnetic forces. This setup can be analyzed with data acquisition equipment to study phenomena such as Poincaré sections, fractal dimensions, and Lyapunov exponents, illustrating the sensitive dependence on initial conditions characteristic of chaotic systems.