This paper presents “ActiveStory Enhanced” as a tool that enables prototyping user interfaces and conducting usability tests in a way that is aligned with agile principles. The tool allows designers to sketch user interface prototypes as well as add basic interactions to provide navigation. Sketching can be done using a mouse or stylus on tablet PCs. Designers can then export the prototype to a web-based Wizard of Oz testing tool, allowing test participants to remotely walk through a UI while recording metrics such as mouse movements and time spent on pages. ASE improves on the original by providing some usability improvements, improved browser support, undo support, more control over the design and an improved pen and paper metaphor.