VideoLAN Client is a free, open-source media player which allows you to view a wide range of multimedia formats starting with DivX, VCD, DVD and ending with CUE/BIN files. Its simple interface makes it very easy to use and the preferences panel contains advanced options for advanced users. Using the program, you can visualise a large variety of multimedia formats without installing extra codec packs. VideoLAN Client preferences give you access to the customization of video and audio filters, codecs, output modules, subtitles, etc. The interface is skinnable and the program has multilanguage support.
Pluses: Some nice features are the Mozilla Plugin, ActiveX plugin, Context Menus and the option to delete preferences and cache. An important advantage is the fact that VideLAN Client comes with all the needed codecs embedded so that you needn't install extra codec packs. You can also watch a stream from a network sent by the VideoLAN Server or another source. The stream can be MPEG 2 TS in UDP or HTTP packets unicasted or multicasted on an IPv4 or IPv6 network.
Drawbacks / flaws:
In conclusion: A complete, reliable and versatile media player. Excellent!