Slides for my 15 minute presentation at Tampere Goes Agile 2013. Abstract: Working software is an expensive way of getting user feedback when compared with role-play or design prototypes. I will present practical examples from the domain of participatory and user-centered design in the context of product and service development. These include various kinds of prototypes, role-play, design games, and simulations. The advantages of these methods include super-fast iterations, committed stakeholders, and ultimately better systems and cheaper IT acquisitions.