If you wanna to play an FLV (Flash Video) file your computer should have installed a video decoder or FLV player, i suggest you to download a FFSHOw Decoder and install on your computer then you can play any kind of FLV and other type of videos in Windows Media player and other players of other platform.
What Phone have you got you can get apps that will do that.
You can watch FLV with Moyea FLV Player. you can download FLV with Moyea YouTube FLV Downloader. You can convert videos to FLV with Flash Video MX Pro. You can convert FLV to Videos with FLV Editor Pro.
An FLV Player is used to play Flash videos that you have saved to your computer. Some of the most popular FLV players include Realplayer, RIVA, VLC and Applian.
Windows media player doesn't support flv format,so you can't play the flv files on it. You can use convert flv files to wmv,avi,mp4,etc. I recommend you 4Media FlV to WMV Converter.It is the professional FLV to WMV converter software which can convert FLV videos to Windows media files including WMV, ASF videos and WMA, WAV, MP3 audios for playing on Windows media players and Windows mobile devices.It's easy to use.You can have a try. You can use VLC player
Currently, RealPlayer 11.0 and up supports FLV file playback. Many other media players such as Windows Media Player with codec pack, QuickTime, VLC Player... also support FLV. get a freeware like sothink flv player So in order to play flv files, an flv player is needed. You can download Aunsoft FLV Player to view flv videos. It's free and easy-to-use. It can open local flv files or those from Youtube, Google Video, Yahoo Video, Myspace, etc.
I think FLV worlks the best. YouTube videos gets converted to FLV when you upload them. When you download the videos, they always come in FLV files.
RealPlayer can support such formts: MP3, WMA, AAC, AC3, MPGE1, FLASH, Realvideo, AVI. Currently, RealPlayer can't play FLV files. Many other media players such as Windows Media Player, QuickTime, VLC Player, Winamp don't support FLV files. So in order to play flv files, an flv player is needed. You can download Aunsoft FLV Player to view flv videos. It's free and easy-to-use. It can open local flv files or those from Youtube, Google Video, Yahoo Video, Myspace, etc.
uSeesoft FLV Converter can do it for you it can convert FLV and YouTube videos to almost any video/audio format with unmatchable conversion speed and high quality, such as converting FLV to WMV, converting FLV to AVI, converting FLV to MP3, converting FLV to MPEG, converting FLV to MP4, etc.
You'd have to download the .flv codec for it. You have other choices such as Winamp to play FLV files as well.
Realplayer or VLC player
get-flv can help to download any videos from the internet, of course from Novamov.