We had a Wiki server wide outage over the weekend but as you can see we are back up! And speaking of backup. I did a backup of the whole MK wiki page. The only part of the data on this page not backed up is the discussion forum. I've no idea why backing up the forum isn't allowed.
I will try and remember to do backups here when needed.
How often? I do try and do it once every few months. Or when a major update is done.