The server that runs this site has endured a minor injury to it’s long term storage (one of the disks, or the RAID card that the disks connect to, are kaput) – fortunately we have backups and a fairly resilient machine, so it’s serving the pages from it’s RAM cache at the moment. The bottom line is that this site will be off line for a little while fairly soon, as soon as we have the opportunity to work out what hardware is at fault, and buy a new one of it.