Body Worlds! Definitely worth seeing if you have the chance. The way they have preserved and displayed these bodies is pretty much dumbfounding. If you haven't attended med school, you'll learn something about your body without being grossed out.
I went at noon on a Saturday and it was a bit crowded, though not really a bit deal. Some exhibits I didn't have the opportunity to scrutinize as much as I would have liked. Most were fine though. My favorite part: seeing the suspended artery networks!