I see. Thanks for clarifying that.

Can they even do that? In order to close-source it, wouldn't they have to remove the Linux kernel and basically rebuild the OS from scratch to keep from violating the GPL?

with a plastic liner & company logo.

Some very good points here, all of which have caused me to rethink my original opinion. In fact, I've decided to change my opinion to the brain over the heart. A line by my favorite actor in one of my favorite movies says it best. "If your head comes away from your neck, it's over." -Sean Connery - Highlander

If any of the others stop functioning (brain-dead, for example), the body still lives. If the heart stops, it's all over.

Teach them real orbital mechanics based on Newtonian physics, using Orbiter Space Flight Simulator, available for free at www.orbitersim.com There is a large supporting community and many available addons, including several vessels from the sci-fi genre. You could teach them how ships really fly in space, as opposed to what they see on the movie screen

His name.....is Robert Paulson.

"We definitely recovered the remains of a flying disk near Roswell, New Mexico."

"It was not a flying disk that was recovered at Roswell. It was in fact a US Air Force weather balloon."

Great. I can see it now. A corporation or government entity will be tasked with maintaining the cosmic shield to protect Earth. We'll all be at the mercy of the Shield Corporation. Can you say "Higlander 2?"