Display a category's TOC
Note that this snippet is for use with the contributed Category module and NOT the core Taxonomy module.
Category module includes category_display which provides a nice Table-Of-Contents for the hierarchy.
This snippet shows you how to include any given category's Table-Of-Contents in any node.
You must know the cid of the category. Go to administer -> categories and move your mouse over the container or the category and write down the id in your browser's status bar.
And here comes the php code snippet:
<?php
$cid = 19; // this is the id you wrote down above
$category = node_load($cid);
print category_display_toc($category);
?>