I do mostly web development, so this would be tricky, but I'd love to see a Balsamiq-like Bootstrap theme, so that you can present a "working wireframe" with the same connotations.
In cases where you perform A/B testing it may require a slick interface, whilst still being a POC. In this case I have looked for ways to reduce complexity and ideally any services which require hosting should be clearly hacked together - such that anyone seeing it can give a clear indication that this will not go into production. Choosing to ignore thread-safety and use local in-memory datastores (e.g. non-persistent) will help to not only ship the POC quickly, but also make its temporary nature rapidly apparent.
