well you could temp put up a index.html and rename the index.php or just add a redirect to the .html via htaccess.. then on the index.html put a message like
"Boards temporily down sorry for any inconvience. We are working to get it up as soon as possible. Please check back later and get a life ya bum. Who is reading these boards anyways, when they are suppose to be working? You are such a slacker.." 
