I've taken to using Shadowbox:
Since one of the things you can bring-up in the box is any external web page, it might meet your need for an image map?
Library Web Services Manager
California State University
From: Code for Libraries [[log in to unmask]] On Behalf Of Ken Irwin [[log in to unmask]]
Sent: Thursday, January 07, 2010 2:20 PM
To: [log in to unmask]
Subject: [CODE4LIB] image maps + lightbox/thickbox/ibox/etc
Does anyone have an-AJAX "pop-up window" style tool that works with image maps? I'm thinking of something in the the lightbox, thickbox, ibox family. I've found a bunch of references to people online *looking* for this functionality, but no one finding it. Any ideas?