Bored? Lonely? Too much work?

Hold a meeting! It's a quick way to get nothing done and make new friends!

That's the joke anyway. Today, I participated in a great meeting. Here's what made it great:
The facilitator/leader knew what was up. She effectively managed the participants ensuring that no one ran away with the meeting. She started on time and made no apologies for those who came late nor made any effort to re-hash for them.
The participants were ready for war. Everyone knew what they brought to the table and shared that. Topics needing discussion and debate got them. Opinions were supported with logic and reason and presented in constructive ways. New ideas bubbled to the surface and were hashed out. Action items were created and defined at the end of the meeting for those in attendance.
It's a great feeling to walk out a good meeting. While not getting anything done, it is empowering to come out of something full of ideas and with a fire to make it happen. Sadly, these good meetings are few and far between. Maybe one day people will change it? What traits do you see in effective meetings?