Netherlanders really like their sex. Prostitution is legal (and unionized!). Just walk into the Red Light District and you'll see things that you never knew existed. But the Sex Museum is perhaps the best examples of the fascination in all of Amsterdam.
For all the hubbub and jokes, the Sex Museum actually takes the subject very seriously. There is a "Sex through History" exhibit, with information that dates back thousands of years. They have myriads of sculptures of naked men and women, but the origins of each and every one are explained. The sex museum is not just there to look at; it's there to learn from, too!
There is a small section that isn't for everyone. It's sort of a fetish explanation area, and some things can get pretty intense and/or disgusting. If you are faint of heart, I wouldn't recommend going into this room!
Overall, the Sex Museum was a fun and unusual experience. My travel partner thought that it would be trashy and not worth it, but she agreed that she learned a lot! We spent about an hour at the museum, so it is well worth the 2€ we spent.