Yeah, that's a great point, and one well worth emphasizing:

Computers don't do anything magical or mysterious, they just do lots of simple things very, very quickly.

If you could somehow slow execution down to the point that they could see individual lines and screen sections being redrawn, pointer positions being calculated, text lines being positioned, etc, it would be a lot less impressive.

Talking about games (something they're familiar with and interested in) gives you a springboard for:
- Graphics (screen drawing, rendering, vector math)
- Physics simulations (particle physics, gravity, collisions)
- Interfaces (Kinect, controllers, touch)
- AI
- Databases
- Networking

Even thought they're interested in games because they're "cool" and "fun," you can use that interest to direct them to the deeper topics behind games. Games intersect with lots of hard, interesting CS topics.

They won't have to police it at our stadium. Drop an extra 70k people in town and you can barely make a cell call for a mile around the stadium, much less get net access inside of it.

There's not much need to spend effort enforcing something that's practically impossible anyway.

My home office desk has wheels, so it's easy to roll back from the wall, and it has a large solid panel in the back. So I screwed velcro strips in to the backside, labeled my wires on both ends and the middle, coiled them up, and strapped them to the back. The only wires that leave the desk are one coax and two power, so my desk is mobile and nearly self-contained, with few visible wires on the front or top.

Admittedly, though, it's also enormous.

I don't condone what Amazon did, and I think they should've gone to bat for their customers, but don't lose sight of what a problem this presents for Amazon's bottom line.

This could render them effectively unable to use any of the Kindle ebook revenue for non-public domain works, since they could conceivably be required to refund all of those funds at the demand of the publishers. They could be forced to collect the money, then just stuff it into an interest-bearing account in case they have to give it back.

So, in effect, we're not even renting the ebooks, we're just giving Amazon an interest-free loan in exchange for getting to borrow the books for a while.

There is a filter approaching that we already know about: the energy filter. I first read this in an SF book, but I don't recall which at the moment (probably either Isaac Asimov or Jack McDevitt). I've since seen the same idea in other places, though.

The basic idea is that not only does it take enormous amounts of energy to leave the planet, it actually takes enormous amounts of energy to harness that energy. Solar, wind, nuclear, and hydro power are great, but you need a base initial amount of easily usable resources to bootstrap them, and on Earth that means fossil fuels. Environmental concerns aside, it seems likely that there's only a relatively small window between the development of fossil fuels and the point at which there are no longer enough fuels left to bootstrap the next stage of energy evolution -- maybe only a few hundred years.

Civilizations that miss that window can begin devolving back through the stages of industrialization, and then exist nearly indefinitely in a pre-industrial state, but they'll never again have the resources necessary to leave their home planet. They will just putter along in a sort of Amish paradise until some natural disaster wipes them out.

That's why alternative energy research is essential. Not for environmental reasons, or political reasons, or economic reasons, or any of the other usual justifications, but because discovering how to make limitless energy via cold fusion doesn't do you any good if you no longer have enough fuels to jumpstart the reaction.