GeeXboX is a free embedded Linux distribution which aims at turning your computer into a so called HTPC (Home Theater PC) or Media Center. Being a standalone LiveCD-based distribution, it's a ready to boot operating system than works on any Pentium-class x86 computer or PowerPC Macintosh, implying no software requirement. You can even use it on a diskless computer, the whole system being loaded in RAM.
Despite his tiny ISO image size, the distribution comes with a complete and automatic hardware detection, not requiring any driver to be added. It supports playback of nearly any kind of audio/video and image files and all known codecs and containers are shipped in, allowing playing them through various physical supports, either being CD, DVD, HDD, LAN or Internet.