Ash Fire provides FirePhp debugging for Magento v-1.7.0.2.
FirePHP is Firefox add-on that enables you to log to your Firebug Console, which makes it great debugging tool for any web developer.
Simple copy the contents of the app folder to your Magento installation.
$firephp = Mage::helper('firephp')->getinstance(true);
$firephp->warn('This is a warning debug message.');
$firephp->info('This is a information debug message.');
$firephp->error('This is a error debug message.');
$firephp->warn($object);