Private progressive download demo.  Progressive download plays almost everywhere and is easy to set up but it has one disadvantage, if the video is heavy, it may stutter on mobile devices.

MP4 Video demo with watermark that displays user name, IP address and date (if logged in, otherwise it displays a USER NOT LOGGED IN message).
This feature is available as a separate script.  See also Dynamic watermark to prevent screen capturing

Below, the same video but with a webm and ogv fallback so that even non-standard mobile devices can play the video as well: