1px by 1px transparent gifs work wonders.
here's an idea of how the bottom of codenewbie works:
PHP Code:
<table border=0 cellspacing=0 cellpadding=0 width=100%>
<tr bgcolor=#000000>
<td height=1><img src=images/spacer.gif width=1 height=1></td>
</tr>
<tr bgcolor=#4B7A3C>
<td align=center>
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</td>
</tr>
<tr bgcolor=#000000>
<td height=1><img src=images/spacer.gif width=1 height=1></td>
</tr>
</table>
i highly recommend putting the size parameters of the spacer image in .. otherwize they might show up like big images before the page completely loads.
css is another option, but i gotta get to work now .. will post an example later.