May I second one of the other poster's suggestions of an egg timer
I belong to a couple of organizations that can have rather long winded business meetings, and if things aren't kept on track the sweet little vague ladies that run those committees can have us so off track that we run hours overtime.
We do our business meeting reminders and minutes via email, so its an easy matter to slip in a notification that each committee will get 2, 10 min. etc for their reports, with additional details via email. It really gets everyone to focus on the crucial issues during reports, and keeps the meeting running at a brisk clip. The organization that I belong to that employs this tactic most often will have a guest speaker after our business meeting, so we need to keep things moving.
The egg timer was introduced during my family member's tenure as president of the statewide organization and was such an aid to keeping the meetings to a reasonable length that the idea has been carried on by other presidents.