As has been said, our shared server has been hacked, all sites on it are down, only IDNetters is showing the banner.
IDNet are working to restore the sites on a new server. I would expect to lose everything after 6am yesterday.
We'd advise all Windows users to do a thorough virus scan of their machines if they've visited the forum.
When we are back up, we'll post here. Once we are running again, I would urge all forum members to change their passwords.