See David Kelley of Wirestone demonstrate his prototype for building immersive retail experiences. As a customer approaches a product, the price tag, display and even the placement wall can all come alive with this integrated application.
a related link:
hackingsilverlight.blogspot.com/.../immersive-ux-changing-face-of-retail.html
and then Ryan's post on the Ardiuno
www.futile.com/.../wpf-sonar-application-using-arduino-and-ping-sensor
anyway we got a better version now that has the price tag ui all fancy and cool looking and working on some cool BI and augmented reality stuff in our UX lab.