Other prototyping techniques that do not fit into the definition of High or Low fidelity categories are:

1. Wizard of Oz technique:  Used to model/mimic functionality of a product by having a human perform the  task usually performed by the computer. The user is unaware that the product is not functional. Usually the “wizard” sits in a back room, observes the user’s actions, and simulates the system’s responses in real-time. For input device testing the “wizard” will typically watch live video feeds from cameras trained on the participant’s hand(s), and simulate the effects of the observed manipulations. Often users are unaware (until after the experiment) that the system was not real.

Advantages:

• Saves time and money when compared to building a functional system.

Disadvantages:

• Setting the stage time.
• Required multiple well trained people
• The user might then have unrealistic expectations.

http://www.usabilitynet.org/tools/wizard.htm

Proof of Concept Video Technique:  fictional video that shows a “working system” in a variety of scenarios.

Metaphor Technique: is meant to help the user build a relevant mental model of how a new design functions. The metaphor communicates the functionality of the novel design compared to systems that the user already knows and is familiar with.