only a douche would hack an index page of a forum, so, I'm guessing Baker. Or Keyser.
Thats the same group that hit my board a couple of years ago.
They don't cause any damage, they just overwrite the index page. They are even nice enough to rename the old index to something like index.bak most of the time.
I think it may be ex employees of the hosting company we use, considering I was the one who recommended this host and my site was hosted here (my test domains still are for bullshit purposes).
it's the old hacker with a heart of gold scenario.