To see the real beauty of the chaotic behaviour you need an oscilloscope. Most of you probably have one, even if you did not realise it. It is possible to use the sound input on your computer as a low frequency oscilloscope which is sufficient for this exercise. Download the Soundcard Oscilloscope. This is a free program which converts the left and right channel from line in, to a two channel oscilloscope. Unfortunately, it is only available for Windows, so you will need to run it in a virtual machine if you are using a Mac or Linux. The oscilloscope is a tool to plot the dynamic behaviour of a circuit and enables us to see how voltages vary over time. Additionally, this oscilloscope enables us to display two inputs against each other in an X-Y mode revealing the nature of the chaotic attractor. Finally, it is even possible to look at the frequency content of the signals.