In fact it is for a forum from a friend of mine for which I do the maintenance, updates and stuff.
He has a couple of forums, a for sale forum and a sold (afgehandeld/verkocht) part.
Posts will be moved to the "sold" forum by moderators and by admins. Once a while he would like to mass-close the posts in the "sold" section. I think maybe because it's a subforum too and it is not displayed as subforum on the main forum page and he does not want it to be displayed. And there won't be any new reply's in that "sold" part.
I thought maybe something like that would be rather easy to make.
But maybe I'm mistaken. In that case he has closed most of them now and if he does a weekly job doing the closing with the build-in option, it would be fine to. But I guess he will forget it again and do the closing in half a year.
So it's no urgent hack or something.