From the HTML::Template docs:

<TMPL_LOOP NAME="FOO">
  <TMPL_IF NAME="__first__">
    This only outputs on the first pass.
  </TMPL_IF>
  
  <TMPL_IF NAME="__odd__">
    This outputs every other pass, on the odd passes.
  </TMPL_IF>
  
  <TMPL_UNLESS NAME="__odd__">
    This outputs every other pass, on the even passes.
  </TMPL_UNLESS>
  
  <TMPL_IF NAME="__inner__">
    This outputs on passes that are neither first nor last.
  </TMPL_IF>
  
  This is pass number <TMPL_VAR NAME="__counter__">.
  
  <TMPL_IF NAME="__last__">
    This only outputs on the last pass.
  </TMPL_IF>
</TMPL_LOOP>
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I reckon that's just about everything you need to pretty up a table. :-)