The Raspberry Pi is extremely suitable to serve all kinds of handy things on your home network that usually would require a server. This is mainly due to its very low power consumption, but also because it is very small and can be hidden in a lot of places. I installed a huge USB stick and the DLNA server MediaTomb. Usually, for embedded use minidlna is recommended. But the Raspberry Pi (at least model B) is more than capable of running the webinterface of MediaTomb as well.

On my (Samsung) SmartTV I can now run my media of off the Raspberry Pi, in MKV even with subtitle support and everything you need :)

If you have more Media Servers running MediaTomb in your network, you should edit the name that is advertised on the network to distinguish them. Edit /etc/mediatomb/config.xml and find the line <name>MediaTomb</name>. Just put your name between <name and </name and restart MediaTomb.