As you can all see, the forum is back up and running.
Thanks go to all involved, including the 3 support people from our webhosting site that I managed to get through this afternoon.
Currently, we're trying to make sure it won't happen again.
Lack of space was a contributing issue. Apparently we've managed to use 9Gb out of 5Gb, stuffed with TF2 replay files

. 63000 to be exact. r007 and mode are taking steps as I write.
Apologies for any inconvenience caused (can't quite think how, but yes)