I'm afraid I didn't see the original posting re: audioguides, but
Tamara Lucas's comments lead me to add the following bit of info:

I recently toured DESIGNING MODERNITY THE ARTS OF REFORM AND
PERSUASION 1885-1945, an excellent exhibition at the Wolfsonian in
Miami Beach.  They utilize an audioguide tour that I found really
augmented my tour.  Rather than force the visitor to adhere to a set
flow pattern, this tour allowed one to listen to information on
whatever object(s) were in front of you.  Object and section areas
had numbers assigned to them, if you were interested in hearing about
that particular object or section, you simply keyed in the
appropriate number(s).  Most of the recorded messages then led one on
to other, related objects or topics.  It was great.  I don't know
which audioguide company the Wolfsonian used, but I'm sure they will
be happy to share that information with you.  Wendy Kaplan is the
exhibition's curator.