In your layout.master file, inside the div id=wrapfooter (or div class="art-footer-text" for Artisteer templates), add the following:
<portal:SiteMapLink id="AnotherSiteMapLink" runat="server" CssClass="sitemaplink" />
id can be set to whatever you want, but it has to be unique (assuming you have this portal control in multiple places).
Jamie