Podcasts (digital audio files) can be utilized creatively to supplement class-room learning. They can be both easily created by instructors and conveniently accessed by students. Students are very receptive to the use of this type of technology as a way to reinforce conceptual understanding of course material. An activity combining a podcast with an active-learning worksheet references the literary classic “The Lord of the Rings” as an analogy to help students understand the many proteins, cells, and processes involved in the human immune response. This activity has helped a significant number of students improve their understanding of this subject.