renderer.js

function template( targetNode, templateNode_ ) {
    var self = {};
    var templateNode = templateNode_ || targetNode;
    var templateString = $( templateNode ).innerHTML.replace( /^\s*<!--/, '' ).replace( /-->\s*$/, '' );
    targetNode.innerHTML = '';
    self.render = function( data ) {
        targetNode.innerHTML = Mustache.to_html( templateString, data );
        return data;
    };
    return self;
}

/* sample: */
var t = template( dojo.byId( 'whatever' ) );
t.render( { to_be_replaced: 'muhkuh' } );

sample.html

<div id="whatever">
    <--
    {{ to_be_replaced }}
    -->
</div>

<-- the template code has to be a comment to prevent the browser from mangling with it -->