I meant to write this up sooner: Elliott, Jon, and I discovered the best weekend activity ever for nerds of all ages. Weekend before last, we went to
Robothon at the Seattle Center and it was great fun. Robothon is an annual event put on by the Seattle Robotics Society. They have vendors and demos and competitions and it runs all weekend.
Elliott's been obsessing about robots for at least a few months now, so it was an easy sell when I told him we were going to get in the car to go and see some REAL LIVE ROBOTS. I think he thought they would be 16 feet tall and have laser guns for arms, but he seemed to be satisfied with the small, peace-loving gadgets we found when we got there.
On the way in, we walked past the International Fountain, a rather odd-looking Seattle landmark especially popular on hot summer days:

This was a gray drizzly day, so I told Elliott that it was the spaceship the robots had used to come to earth. He was very enthusiastic about that story.
At the event itself, there was plenty to look at, but my favorite part was the
MicroMouse competition. Here's an example of a MicroMouse maze (not the one I saw, just a random one from the web):

Each robot had ten minutes to explore the maze and make runs from the start corner to the center of the maze. The fastest run within that ten minutes would be the final time.
There was a big variety in the robots that ran the race. One was built from stock, off-the-shelf Lego Mindstorms components; another was almost completely hand-crafted from specialized components and circuit boards. Strategies varied a lot too. The Lego robot just followed walls, but the fancy circuit board robot mapped the entire maze with four downward-pointing "eyes," charted an optimal route, and then made speed runs to the center.
It was a great event for all of us and I hope we manage to attend again next year. Maybe one of these years I'll build a robot and bring it along, too -- or if all else fails, I'll check at the International Fountain and see if any robots newly arrived from space want to join forces with me.