cache.xml

<?xml version="1.0"?>
<config>
	<placeholders>
		<your_modules_holepunch_node>
			<block>your_module/your_block</block>
			<name>layout.name.for.your.block</name>
			<container>Your_Module_Model_Container</container>
			<placeholder>PLACEHOLDER_NAME_FOR_YOUR_CONTAINER</placeholder>
		</your_modules_holepunch_node>
	</placeholders>
</config>

container.php

<?php

class Your_Module_Model_Container extends Enterprise_PageCache_Model_Container_Abstract
{
    /**
     * Override this method and return false to prevent block from being cached
     * @param string
     * @return bool
     */
    public function applyWithoutApp(&$content)
    {
        return false;
    }

    public function applyInApp(&$content)
    {
        $blockClass = $this->_placeholder->getAttribute('block');
        $template = $this->_placeholder->getAttribute('template');
        $blockContent = $this->getBlockContent(new $blockClass, $template);

        $this->_applyToContent($content, $blockContent);

        return true;
    }

    /**
     * @param Mage_Core_Block_Template
     * @param string
     * @return string
     */
    protected function getBlockContent(Mage_Core_Block_Template $block, $template)
    {
        $block->setLayout(Mage::app()->getLayout());
        return $block->setTemplate($template)->toHtml();
    }
}

gistfile1.txt

To holepunch a template, you need:

1. Cache config. (just add cache.xml to your modules /etc/ folder)

2. A container. (just rename the class; the content of the methods just render your block)