Universal Media Server

Universal Media Server is a media server capable of serving videos, audio and images to any DLNA-capable device.
It is totally free, regularly updated and has more features than any other media server, including paid ones.
It streams to many devices including PS3, Xbox 360, many TVs (Samsung, Panasonic, Sony, Vizio, LG, Philips, Sharp), smart phones (iPhone, Android, etc.), Blu-ray players, and more.