The wiki is back online, and the archive is being uploaded anew as I write this (it will probably take a few hours to complete).
My sincere apologies to everyone who has been waiting. This should not happen again, as long as I don't meddle with things. So little work was needed, it's embarrassing that it took so long!
PS: It may very well be true that phpBB forums are popular hacker targets, and I'll try to make sure that this forum stays on the most recent software release, or at least reasonably recent. Let me know if I fall too far behind!