E = mc2. It's hands-down the most well known equation out there. But how many have the faintest idea what the equation really means? Not too long ago, PBS' NOVA put together a "docudrama," called Einstein's Big Idea, which took a close look at how Einstein arrived at the equation and what it means. Along with the program, NOVA produced some related media resources, among which you'll find a series of podcasts (iTunes - Feed - mp3) featuring 10 top physicists (including two Nobel Prize winners) who briefly explain the meaning and importance of E = mc2. In addition, and perhaps even better, they've posted an audio clip of Einstein himself explaining what the equation is all about. You'll find many good resources here, so have a good look around.
If physics intrigues you, you should also check out a new Stanford course that's being distributed for free via video podcast. The course, Modern Theoretical Physics: Quantum Entanglement, is presented by Leonard Susskind, whom many consider the father of string theory, a controversial innovation in physics that squares quantum theory with relativity and explains the nature of all matter and forces. Now, when Susskind discusses quantum entanglement, he is surely getting into some heady, cutting-edge stuff. But the good thing is that the very popular course was presented through Stanford's Continuing Studies Program (where I work, just to put my cards on the table), and was geared toward the general public. The course is expected to last a full year, and it should result in 30 free two-hour lectures, which will all be gradually posted online. You can find a more detailed course description here.