FLVPlayer HD is a cross-platform FLV(Flash Video) media player developed on Adobe Air. Ofcourse VLC Media Player, Media Player Classic, GOM Player, etc are all able to play flv video files, even the default Windows Media Player in Windows 7 can play .flv format. But in some cases(very few) if the video or audio is lagging, then you can give FLVPlayer HD a shot.
It has a simple interface where you can play the video files by either manually opening it or dragging&dropping any flv file. You can Play/Pause the video, move the slider to jump anywhere in the video, change volume, and switch to full screen, all-in-all it contains some very basic functions only.
One feature that stands out is the seamless online streaming of flv video file. Enter a URL of flv video file and it will start streaming instantly.
It can play flv videos in HD format as well. The developer plans to add more functionality in the next release.
Since it is developed on Adobe Air, it can be installed on Windows, Mac, and Linux.