The most POPULAR stream recording software (free download):

• REPLAY MEDIA CATCHER
  the best audio/video stream ripper. Supports the most popular flash video format (RTMP and HTTP).
• REPLAY CAPTURE SUITE
  the best audio/video stream recording/capturing bundle
• REPLAY MUSIC
  the best streaming music recorder
• WM RECORDER
  the best Windows Media, Real Audio/Video stream capture software

Other RECOMMENDED software and services:

• REPLAY MEDIA GUIDE
  free service to find and record online radio, Internet TV, podcasts
• AVS VIDEO TOOLS
  convert, split, join, remove commercials, edit, rotate, apply effects, capture, transfer, copy, rip and burn DVD and video files
• EMUSIC
  the best legal music download service
• AUDIBLE
  download audio books, audio magazines, newspapers, radio programs
• SOUNDTAXI
  remove DRM protection from Windows Media, iTunes music and video files

Play flash videos with Media Player Classic or any DirectShow supporting player

Freeware K-Lite Codec Pack (Windows) has an FLV splitter so after installing it you will be able to play .FLV files with Windows Media Player, free Media Player Classic or any other DirectShow-supporting player.

When installing K-Lite Codec Pack don't forget to mark "FLV Splitter" (DirectShow source filter) among the installed components. You will also need to mark ffdshow decoder to decode video and some DirectShow audio filters to decode audio (Usually the default options will suit you OK. If you don't wanna keep them, make sure you understand what you are doing.)

Among additional tasks for setup to perform find the "Decode the following video formats with ffdshow" group and mark the "FLV1" option.

After installing double click a .FLV file to play.

P.S. This was tested with K-Lite Codec Pack 2.71f. The result was much more stable than with any other FLV player tested before.

Play flash videos with Free FLV Player by Martijn de Visser

1. Download and install freeware FLV Player by Martijn de Visser. Note that it is available for Windows platform only.
   If you already have Replay A/V or Replay Media Catcher installed (it can be used to record .FLV videos easily), then FLV player is already loaded for you.
2. Locate the FLV file using File Explorer. If you've used Replay A/V, click the Show you've captured, then click the View button.
3. Double click the .FLV file. It begins playing in FLV Player.

Playing .FLV videos with free VLC Player

Other options to play flash video .FLV files