I was thinking to start a new forum. But I want the forum to be lite. By lite I mean to use less space, bandwidth and database. I have some scripts in mind - punbb, fluxbb, usebb, vanilla, minibb, bbpress. So far the one I like is punbb. I hear it has a cleaner code than fluxbb - I am not sure about this. Vanilla and minibb doesn't feel that good. But I would like to have an opinion from everyone before I go ahead with this.
I don't know the answer, but you probably should ask the question here http://www.theadminzone.com/forums/index.php as this is a forum about operating a forum and they cover lots of systems. Let us know what you settle on. I'm curious myself.
I've used MiniBB for a project before but have also heard really good things about Vanilla Forums. I think you should try a couple out and see what you prefer, after all they will have broadly the same features.