We are experiencing some problems with our upstream hosting provider, resulting in an outage to the service. We’re waiting for our hosting provider to rectify the issue. We’ll update here when we know more.
UPDATE : It appears to be a failed SAN disk, resulting in a general performance degradation. The disk is being replaced at the moment.
UPDATE2: The failed disk has been replaced and the storage array is rebuilding, this means the site may be a little slow until this operation completes, but it is now available again.