DestroY MediaPlay is one hell of a flexible media player - it plays video, audio files, DVDs and can even display and play music online.
Not only this, but it features a mini web browser with which you can surf the net. It terms of flexibility, this player is hard to beat. The list of formats it can play is seemingly endless including asf, asx, wav, wma, wmv, ogg, mpg, mpeg and snd amongst many many others. The DVD players is also pretty impressive featuring full support for CDDB so there's no need to label your tracks manually once they are converted to mp3 format. The players also supports some audio streaming although it's designed mainly for SHOUTcast and Icecast streams.
The interface is pretty cool for a free player although it seems like there are only 7 alternatives to the default skin. However, there is an effective Spectrum Analyzer and Oscilloscope plus it supports Drag & Dropping of tracks plus the scheduling of tracks. This can be done by track number, date and up to a set limit of daily, weekly or monthly. In addition to all this, there are hotkeys configurable and you can type in the lyrics for your own karaoke sessions. Add this to an ID3V1/V2 & OGG tag editor, DirectX sound effects and Playlist HTML export and you have a pretty impressive package.
A very comprehensive and modern looking player but it could do with some more skins and slightly more streaming support.