I encountered an interesting phenomenon last week waiting in the car-pool line at my son’s school. It was a 95° day, yet in spite that, I don’t like to let the car run for 15 minutes while waiting for school to let out, so I put the windows down and turned off the vehicle. I was sitting there reading and I felt a vibration in my feet, so much that I checked that my car was indeed off. I felt the door and the dash and could feel the vibration there as well. It took a couple of minutes to realize that the vibration I was sensing was from the other cars in the car-pool line, running, with their air conditioners on. Imagine that vibration on a global scale – can our presence be felt elsewhere in the universe, and if so, can we likewise detect other civilizations by their vibrations?