I was struggling here. Even this research, though interesting, is as whacky as Professor Brainstrom. The reality is a smatphone and an earpiece. Indeed theree are museums that offer an iTouch for visits.
Any other ideas for 'Z' ?
Zimmermann, A, & Lorenz, A 2008, 'LISTEN: a user-adaptive audio-augmented museum guide',User Modeling & User-Adapted Interaction, 18, 5, pp. 389-416, Business Source Complete, EBSCOhost, viewed 28 October 2013.