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Provides a multi-layer navigation block based on a single vocabulary.

It was written as a replacement for the jsdomenu module, which makes extremely heavy use of javascript and tends to slow down page loads on older browsers or machines. This module is almost entirely based on XHTML and CSS. You can see an explanation of how all the ideas in this work on the demo site (not my work, I just plagiarised it!)
This module is no longer active since it has been superseded in my view by Nice Menus which works better and is simpler