"The Fifth Dimension: It's Closer Than You Think" Over the past two years, there has been an explosion of interest in theories with large extra spacetime dimensions. Growing numbers of theorists and experimentalists are actively exploring the possibility that extra curled-up spacetime dimensions might soon be discovered, either in the next round of collider experiments, or in table-top Cavendish experiments. This recent interest in extra dimensions stems largely from the realization that extra spacetime dimensions have the potential to lower the fundamental high-energy scales of physics (such as the GUT, Planck, and string scales), perhaps making them experimentally accessible for the first time. If this theoretical possibility is realized, we might soon be able to probe the novel physics of grand unification, quantum gravity, and even string theory experimentally. In this talk, I will provide a non-technical survey of these recent ideas, and discuss how and why large extra spacetime dimensions can lead to such exciting physical possibilities.