This morning’s RE12 keynote was excellent. Steve Fickas described his use of a gaming engine and other resources to create a virtual environment for testing / requirement elicitation for mobile devices.
Fickas went on to describe how he interfaced mobile devices under development to the virtual environment and use this for testing in early stage development iterations (it is more controlled / manageable than the real world)
you can now watch this keynote
Just added the background why this is so great in this post: killing or curing with users.