The video was avi you are in luck.
http://www.whispergen.com...vid_avi_10mb.avi
It's operational in hotels where there are huge water heaters so on. There's a small home unit by whispergen which I think generates 1000watts but it depends on how much water you are heating and goes back to the grid. It turns off when not in use and I believe uses some power to start up so not worth it for say 1 person on their own.
There are figures so on that people have for these units which you can easily google.