We bring vexbots for kids to drive (and then we play the "go hit that guy in the brown shirt" game). Our demo-bot is our '07 bot. At our last demo (with 1732), we had kids feed tubes to the robot and put them on part of this year's rack. Kids really liked "feeding" the robots.
If you have/sell hexbugs, we sometimes have those running around too.
Also: BUTTON MAKING STATION! Get some extra button supplies and have kids make buttons.
