SVG
It is also high-performance
SVG Viewer for Internet Explorer that enhances the SVG 1.1 Tiny specification.
SVG Map Toolkit can be downloaded from the following link. http://blog.svg-map.com/2007/12/svg_map_toolkit.html
Moreover, the world SVG map based on VMAP can be browsed from the following link.
http://blog.svg-map.com/2007/11/tiny_svg_base_m.html
This map is scrollable and zoomable. And, In a part of region in Japan,
1:25000 scale map that Geographical Survey Institute of
Japan is publishing will be able to be browsed by zooming up.