$craftPath multiple enviroments
There is a really nice multi-environment configuration method defined on the craft cookbook website, that creates a global php variable called CRAFT_ENVIRONMENT in your main index.php. It seems to me that you could also use this global to define the $craftPath.

switch (CRAFT_ENVIRONMENT) {
    case "dev":
        $craftPath = '../craft';
        break;
    case "stage":
        $craftPath = '../../craft';
        break;
    default:
        // default "production"
        $craftPath = '../../craft';
}


I generally use the above method (without the new switch part) in combination with this configuration method in my general.php config file.