My favorite part was going in the building where they are working on sections of the new space station. We can see shuttle launches from the house, and the launch last week carrying the Destiny module was one of the most spectacular I've ever seen. The sun was at that perfect golden stage, and the angle of the launch made it possible to view for a very long time. Really cool!
They were working on the section of the space station called Leonardo - it will be great fun to keep track of when that section goes up, since we got to see it up close and personal. :)