Spoken interaction between humans and machines has long been a goal of scientists and engineers. As computational devices continue to shrink in size, speech-based interfaces are more relevant than ever. At the same time, audio and video media are fast becoming significant data types themselves. Without additional processing however, searching these materials can be tedious. Spoken language technology offers the opportunity to provide structure for more effective browsing, summarization, and even translation. This presentation will provide an overview of ongoing research in the MIT Computer Science and Artificial Intelligence Laboratory to enable accessible, multimodal, customizable, and context-aware speech-based interfaces. There will also be a presentation of recent activities in spoken lecture processing which attempt to transcribe and index academic lecture recordings, including web-based demonstrations of recently developed interface and content processing prototypes.