I work with this one guy. In his cube, he has a coffee mug that says, "I survived another meeting that should have been an email."

Have people prepare, sure. Cut down on un-necessary people, sure. Focus the meeting on one thing, which leads to shorter meetings, sure. But best of all, don't have the meeting if you can help it. Only have a meeting for what you can't do by email (or can't do without major inefficiency).