VLC media player is an open source video and audio player capable of playing almost any type of media including DVDs and VCDs. In addition to being able to play most video and audio files, VLC can also post free ads without registration
File extensions that can be opened by vlc-media-player

oa.ASX	Advanced Stream Redirector
oa.DTS	Digital Theater Systems Audio File
oa.GXF	General eXchange Format
oa.M2V	MPEG-2 Video
oa.M3U	MP3 Uniform Resource Locator
oa.M4V	MPEG-4 Video File
oa.MPEG1	MPEG-1 Video
oa.MPEG2	MPEG-2 Video
oa.MTS	AVCHD Video File
oa.MXF	Material eXchange Format
oa.OGM	Ogg Multimedia Container File
oa.PLS	Playlist
oa.BUP	DVD Information File
oa.A52	Dolby Digital AC-3 Compressed Audio File
oa.AAC	Advanced Audio Coding Compressed Audio File
oa.B4S	Winamp 3+ Playlist
oa.CUE	Cue Sheet
oa.DIVX	DivX Movie
oa.DV	Digital Video
oa.FLV	Flash Video
oa.M1V	MPEG-1 Video
oa.M2TS	MPEG-2 Transport Stream Videos
oa.MKV	Matroska Video Stream
oa.MOV	Apple QuickTime Movie
oa.MPEG4	MPEG-4 Video
oa.OMA	OpenMG Audio File
oa.SPX	Ogg Speex Audio File
oa.TS	DVD Video
oa.VLC	VLC Media Player Data
oa.VOB	DVD Video Object
oa.XSPF	XML Shareable Playlist Format
oa.DAT	VCD Video
oa.BIN	Binary DVD Video
oa.IFO	DVD Information File
oa.PART	Partially Downloaded File
oa.3G2	3G Mobile Phone Video
oa.AVI	Audio Video Interleave
oa.MPEG	MPEG Video
oa.MPG	MPEG Video
oa.FLAC	Free Lossless Audio Codec Compressed Audio FIle
oa.M4A	MPEG-4 Audio File
oa.MP1	MPEG-1 Audio Layer I
oa.OGG	Ogg Multimedia Container File
oa.WAV	Waveform Audio
oa.XM	Extended Module Audio File
oa.3GP	3G Mobile Phone Video
oa.SRT	DVD Subtitles File
oa.WMV	Windows Media Video
oa.AC3	Dolby Digital AC-3 Compressed Audio File
oa.ASF	Advanced Systems Format Video
oa.MOD	MOD Audio File
oa.MP2	MPEG-1 Audio Layer II
oa.MP3	MPEG-1 Audio Layer 3
oa.MP4	MPEG-4 Part 14 Multimedia Container
oa.WMA	Windows Media Audio File
oa.MKA	Matroska Audio Stream
oa.M4P	Protected AAC File

aoa   boa   coa   doa   eoa   foa   goa   hoa   ioa   joa   koa   loa   moa   noa   ooa   poa   qoa   roa   soa   toa   uoa   voa   woa   xoa   yoa   zoa   0oa   1oa   2oa   3oa   4oa   5oa   6oa   7oa   8oa   9oa