Lots of assorted links listed here for now but will soon have notes attached to them about content description, highlights.
Special Support KML, shapefile support
The Map View in here has an advanced menu control http://www.360sardinia.net/itineries.php?tour=34&pos=1&ipix=70506
not sure about… http://www.kamelwriter.com/
need to study this closer… http://www.opengeospatial.org/projects/groups/gmlwg
also see: http://developer.yahoo.com/yui/ (the yahoo user interface), and * http://www.jackslocum.com/blog/index.php he is writing yui-ext, (very good stuff his page is worth looking at, and he gives away the tools he used to build it)
These are the tool that used to build the interface.