Foobar2000 Media Player is a very very recommendable player. It is developed by Peter Pawlowski who is or used to work on Winamp3.
FB2000 uses a plain and simple UI - no skins, no fuss. Filesize is 200 kb, while in playback mode the player approximately consumes 1.9 Mbyte of your RAM which is so much less compared to Winamp or MS Media Player.

Foobar2000 is an advanced audio player for the Windows platform.


Key features :
· Open component architecture allowing third-party developers to extend functionality of the player
· Audio formats supported "out-of-the-box": WAV, AIFF, VOC, AU, SND, Ogg Vorbis, MPC, MP2, MP3, MPEG-4 AAC
· Audio formats supported through official addons: FLAC, OggFLAC, Monkey's Audio, WavPack, Speex, CDDA, TFMX, SPC, various MOD types; extraction on-the-fly from RAR, 7-ZIP & ZIP archives
· Full Unicode support on Windows NT
· ReplayGain support
· Low memory footprint, efficient handling of really large playlists
· Advanced file info processing capabilities (generic file info box and masstagger)
· Highly customizable playlist display
· Customizable keyboard shortcuts
· Most of standard components are opensourced under BSD license (source included with the SDK)

http://www.foobar2000.org/index.html