Took my son to see the Terracotta Warriors exhibit on Memorial Day. We loved it. I still remember the first time I heard of the first Chinese emperor's terracotta army -- from an article in National Geographic back when I was a kid.
Also on view was an exhibit about spying and espionage. We loved that, too -- very interactive, including a room full of crisscrossed, changing, green security lasers that you have to navigate through in twenty seconds. No crowd, so my son must have tried it about ten times. I tried twice. Some other great interactive stuff, and lots of amazing spy artifacts, especially from WWII and the Cold War. Turns out you can put a camera in just about anything, from a glue stick to a robot dragonfly. Fascinating stuff, and highly recommended. Tix are a bit pricy, but well worth the splurge.