Plex Media Server is a great server for playing media (tv, movies, pictures) on a variety of devices (Android, Roku, Smart TVs, Windows, Mac, IOS, etc). It supports transcoding, a very nice interface layout, tracks what episodes or movies you have already watched, share with your friends and with a plus pass (paid account) there are additional features as well such as sync so your device can sync when you are at home and let you play when you are mobile without using data to watch.
There is a third party repo that seems to be updated quite often (as of this article anyway) for Debian Squeeze and Wheezy. To use it, the instructions are pretty simple:
sudo apt-get install curl echo "deb http://shell.ninthgate.se/packages/debian squeeze main" | sudo tee -a /etc/apt/sources.list.d/plexmediaserver.list sudo curl http://shell.ninthgate.se/packages/shell-ninthgate-se-keyring.key | sudo apt-key add - sudo apt-get update sudo apt-get install plexmediaserver
Your server should now be installed and functional. The default port is 32400 for the web interface, so to manage it you can go to http://192.168.0.5:32400/web/ (change your ip as needed) and add in your media files. Have fun :)