I just bumped into to this lovely video tour of a website called Tipspot. Basically a low fidelity representation of the interface and the story, in which all elements are cut out of cardboard. Might be very time consuming, but it does look great!

http://www.tipspot.com/about/tour

This (and the rest of the videos above) can all be done with iMovie and a digital camcorder. If you want to get fancy, you can use a tripod Since the RaMo video uses a split screen at one point, my guess is they used Adobe Premier or Final Cut Express.

When making a video prototype, it’s important not to get caught up in “film making”. It has been my experience that limiting yourself to software such as iMovie is a good constraint that will make you focus on the task at hand… prototyping.