I have disabled and then deleted a couple of plugins and then my site stopped working. Or it might have stopped working for some other reason...i don't know am completely stumpped.
But I have worked it back to this line of code:
apply_filters('the_content', $content);
in post-template.php. When it is commented out the site works but none of the plugins appear.
This also happens with the_excerpt method, so I think it might be further into the code, possibly this line of code:
$value = call_user_func_array($the_['function'], array_slice($args, 1, (int) $the_['accepted_args']));
But I have no idea. Do you?