In this talk we provide a practical introduction to Acoustic Cryptanalysis using tools and techniques that are easily grasped and cheaply available. The intention is not to present any new results, but instead the emphasis is on gaining a foundation in the theory of such attacks, so that you will be able to apply them more effectively in more challenging scenarios. As we shall see, such attacks are an extension of other types of side-channel attack (timing and power analysis attacks in particular), with the added promise of bridging air gaps.