Producing a Table of Contents

When doing a transformation, is there any 'clever' way of generating a 
table of contents in the XSLT based on the actual content of the 
template?

For example, the template has lots of sections of text preceded with 
headings (using <h1></h1> tags).  Using XSLT is it possible to search 
through the template to draw up a list of the text between these tags?
-- 
Cheers,

Julian Voelcker
United Kingdom