Sex Museum, Amsterdam
A city like AMS with its big and famous red light district must have a "sex musem" as well, I guess. There is also an "Erotic museum" right in the red light zone, but we didn´t visit that. The sex museum gives some quite funny and nice impressions of sex in the world through the history.
2012 LH Amsterdam
"Five floors of highly suggestive trinkets and photos" is probably a better description than "museum." If you're in a when-in-Rome mood, you may want to choose to visit here. Happily, it is all presented rather lightheartedly (although animal-lovers should steer clear of the snapshot gallery). Beatles fans should note that there is an original and satisfyingly suggestive sketch by John Lennon, perhaps rendered when he and Yoko did their weeklong bed-in for peace at the Hilton. Camp fans should note that there is a rich collection dedicated to the patent-leather-clad 1950s muse and proto-dominatrix Betty Page.
The sex museum is pretty close to the central train station. I didn't go in, but they have a couple of statues in the front that you can see for free.