JustSubsPlayer is free software to add subtitle on online streaming video. Unlike other software, it does not require a video file, so it can be used to add subtitles to online movies or TV series, even if they are flash-based videos.

SopCast is a simple, free way to broadcast video and audio or watch the video and listen to radio on the Internet.

More resources:

PS:  If we want to use more real free applications (not pay), we probably need to save some brilliant free applications by (a) keep using them and give feedback to help improve it; (b) spread your own use experience and help increase its recognition.