Will 1/3 of you please stand up and leave the room

Let's suppose you're running a meeting with, say, 30 people or more. You look around the room and see that 1/3 of the people are doing IM, email, surfing, doing the blackberry, etc. It's fairly easy to tell those from the people that are using their laptops to take notes. What can you conclude?

1. 1/3 of the people didn't need to be invited - you've got too many people there

2. You'll take a 1/3 hit on productivity, because you'll be explaining things again

3. You're agenda isn't resulting in action and the meeting is probably just the mutual sharing of profound ignorance.

Just getting people together face to face to 'just get this thing done' doesn't work, and getting 'everyone together' is usually a waste of time and resources unless they all walk away with action. Sure 'sharing' and 'getting everyone on the same page' has value, but at what cost?

If you're in a meeting, doing IM, email, blackberry, surfing, etc. it's not okay. It's unprofessional. It's rude. It's a waste of company resource. No, you can't effectively multi-task. No, you're not that important. You send the message that the other person's time is not valuable.