The web is exploding with new media, and more and more people are interested in open source tools for delivering and consuming webcasts, videocasts, webinars, streaming audio, podcasts and more. The good news is that the open source community has responded with all the tools you need to create and consume video- and audio-based rich media at no cost to you. In the world of commercial software applications, the proprietary equivalents can cost you thousands of dollars. Here are 15 great, free, open source tools that can make you a broadcaster.