library/
  Core/
    Controller/
      Action/
        Helper/
          GetModel.php
  Zend/

/**
 * Core Library
 *
 * @category   Core
 * @package    Core_Controller
 * @author     Federico Cargnelutti <fede.carg@gmail.com>
 * @license    New BSD License
 */
 
/** Zend_Controller_Action_Helper_Abstract */
require_once 'Zend/Controller/Action/Helper/Abstract.php';
 
/**
 * @category   Core
 * @package    Core_Controller
 * @author     Federico Cargnelutti <fede.carg@gmail.com>
 * @license    New BSD License
 */
class Core_Controller_Action_Helper_GetModel extends Zend_Controller_Action_Helper_Abstract
{
    /**
     * Zend_Registry instance
     * @var Zend_Registry
     */
    protected $_container;
 
    /**
     * Return a single instance of the model object
     *
     * @param string $filename Filename.
     * @param null|string $module Module name.
     * @return object
     */
    public function getModel($filename, $module = null)
    {
        if ($module === null) {
            $module = $this->getRequest()->getModuleName();
        }
 
        $class = (string) ucfirst($module)  . '_' . $filename;
        if (!$this->getContainer()->isRegistered($class)) {
            $moduleDir = $this->getFrontController()->getControllerDirectory($module);
            if ($moduleDir === null) {
                /** Zend_Controller_Action_Exception */
                require_once 'Zend/Controller/Action/Exception.php';
                throw new Zend_Controller_Action_Exception($module . ': The requested module does not exist.');
            }
            $modelDir = dirname($moduleDir) . DIRECTORY_SEPARATOR . 'models';
 
            $file = $filename . '.php';
            Zend_Loader::loadFile($file, $modelDir, true);
 
            $model = new $class;
            $this->getContainer()->set($class, $model);
        }
 
        return $this->getContainer()->get($class);
    }
 
    /**
     * Call helper as broker method
     * 
     * @param string $class Class name.
     * @param null|string $module Module name.
     * @return object
     */
    public function direct($class, $module = null)
    {
        return $this->getModel($class, $module);
    }
 
    /**
     * Retrieve container
     *
     * @return Zend_Registry
     */
    public function getContainer()
    {
        if ($this->_container === null) {
            require_once 'Zend/Registry.php';
            $this->_container = Zend_Registry::getInstance();
        }
        return $this->_container; 
    }
 
    /**
     * Set the container instance
     *
     * @param Zend_Registry $container
     * @return Core_Controller_Action_Helper_GetModel
     */
    public function setContainer(Zend_Registry $container)
    {
        $this->_container = $container;
        return $this;
    }
}

Zend_Controller_Action_HelperBroker::addPrefix('Core_Controller_Action_Helper');

class Default_IndexModel extends Zend_Db_Table
{
    protected $_name = 'default';
}

class Default_IndexController extends Zend_Controller_Action
{
    public function indexAction()
    {
        $model = $this->_helper->getModel('IndexModel');
        $sharedModel = $this->_helper->getModel('PostsModel', 'blog');
    }
}

library/
  Core/
    Controller/
      Action.php
  Zend/

/**
 * Core Library
 *
 * @category   Core
 * @package    Core_Controller
 * @author     Federico Cargnelutti <fede.carg@gmail.com>
 * @license    New BSD License
 */
 
/** Zend_Controller_Action */
require_once 'Zend/Controller/Action.php';
 
/**
 * @category   Core
 * @package    Core_Controller
 * @author     Federico Cargnelutti <fede.carg@gmail.com>
 * @license    New BSD License
 */
class Core_Controller_Action extends Zend_Controller_Action
{
    /**
     * Zend_Registry instance
     * @var Zend_Registry
     */
    protected $_container;
 
    /**
     * Return a single instance of the model object
     *
     * @param string $filename Filename.
     * @param null|string $module Module name.
     * @return object
     */
    public function getModel($filename, $module = null)
    {
        if ($module === null) {
            $module = $this->getRequest()->getModuleName();
        }
 
        $class = (string) ucfirst($module)  . '_' . $filename;
        if (!$this->getContainer()->isRegistered($class)) {
            $moduleDir = $this->getFrontController()->getControllerDirectory($module);
            if ($moduleDir === null) {
                /** Zend_Controller_Action_Exception */
                require_once 'Zend/Controller/Action/Exception.php';
                throw new Zend_Controller_Action_Exception($module . ': The requested module does not exist.');
            }
            $modelDir = dirname($moduleDir) . DIRECTORY_SEPARATOR . 'models';
 
            $file = $filename . '.php';
            Zend_Loader::loadFile($file, $modelDir, true);
 
            $model = new $class;
            $this->getContainer()->set($class, $model);
        }
 
        return $this->getContainer()->get($class);
    }
 
    /**
     * Retrieve container
     *
     * @return Zend_Registry
     */
    public function getContainer()
    {
        if ($this->_container === null) {
            require_once 'Zend/Registry.php';
            $this->_container = Zend_Registry::getInstance();
        }
        return $this->_container; 
    }
 
    /**
     * Set the container instance
     *
     * @param Zend_Registry $container
     * @return Core_Controller_Action
     */
    public function setContainer(Zend_Registry $container)
    {
        $this->_container = $container;
        return $this;
    }
}

class Default_IndexModel extends Zend_Db_Table
{
    protected $_name = 'default';
}

class Default_IndexController extends Core_Controller_Action
{
    public function indexAction()
    {
        $model = $this->getModel('IndexModel');
        $sharedModel = $this->getModel('PostsModel', 'blog');
    }
}