I've been playing on a server that has been having a lot of issues lately. (It keeps crashing, and needs a manual restart each time.) I got frustrated at trying to connect every five minute, and so wrote a small python script to poll the server to see if the server is online. I shared in in the server thread, but decided to post this here as well, in case anyone else wanted to use it.
Download here. (Sorry about the egregious size (well, 1.8MB) - It includes both the python script and an exe version)
You have to enter the server address in address:port form (240.0.0.2:25585; www.google.com:80, etc.), as I have not spent much time on it. It will beep at you until you kill the program (press Control-C) once the server is online. By default it only checks every minute, to avoid overloading the server, and stops once a successful check has been made.
Also, standard liability limitations apply. If it stomps you flat and eats your hat, that's your problem.