Website software
* Get Amount of hashing per second of the entire farm, and individual
* Shutdown
* if there is a hardware failure be notified by email and show popup thru the site (using ajax and querying a php script every 5mins)
* Dashboard that doesn't need to be refreshed


Why you need desktop software, I would have everything running thru the website, your probably going to need background software processes to get the information to the mysql database.