Somewhat strange: now that I get regularly moments for the forum working without lag, quite a lot of you seem to get the problem of not being able to access the forum. Some time ago it had been vice versa...
Anyway, IIRC Andi said, I don't know exactly, that he arranged something that should get into work sometime. (I know, my expresions are very vague, but I don't know exactly either.)
Hopefully it works, in case not, I might perhaps be able to offer a section of a forum as well, it's vBulletin, not the standard style. However, I'm not a fan of moving to another forum overall, mainly because the old information (i.e. threads) cannot easily moved over to a new forum, since afaik conversion is not completely working yet.
To avoid that, another option would be to create a new YaBB board, but since the Invision board seemed to work on this server, I think the problem is the forum system rather than the server; therefore I hope the new version, or whatever it is (as I said, I don't remember exactly) will work better.