Dan Marlin tells us that Project Mayo has unleashed "OpenDivX," an MPEG-4 compliant natural video encoder and a decoder.
"OpenDivX is the mothership of all ProjectMayo projects. This is an Open Source project that at it's core will consist of a compliant MPEG-4 natural video encoder and a decoder. There are also other projects that are springing up under the OpenDivX roof. Including "The Playa" Which is an open source player for DivX. It includes advanced features like progressive download (unlike the old DivX ;-)) and plays "broken" or uncompleted video files. The first version will be on Windows but they are also planning Linux and Mac versions." Read more at projectmayo.com.