One of the more fascinating prototyping techniques that was mentioned this week was bodystorming 1 which I had never heard of.
After reading about it though I have actually done something similar and do advocate this method.
Quite often in my current role, when we offer a client a new service I go out to site with our work teams and watch them carry out this new service on site, and pick up working habits and rituals and design the software to work around these patterns, as it makes the software easier to understand and more efficient.
As stated though, one of the key drawbacks to this is that it is more time-consuming than other methods, and as such is difficult to work into rapid ideation (RI) scenarios.