Never had one due to this trick I borrowed from an old friend.
So we all know about those meetings where its all crap flying around right?.
First go in there with your alarm clock set on vibration every 7 minutes(trust me on this-makes you look important and you ought to be somewhere else)
Actually the alarm is a reminder that you need to bring yourself back online.
At this point just listen to the speaker for a couple of seconds(especially if its marketing dept) and being the engineer your are; rephrase parts of their presentation in a question-comment hybrid( at this point you're the wisest looking person in the room)
Now go back to thinking about that pizza slice you left in the fridge as they discuss the "lean production" methods that they can use based on "your opinion"..
To more happy meetings..cheers