Gone Dutch

Due to the fact that it will be the run up to my birthday, and mostly because the grandparents have very bravely elected to have the kids for four days, the Wife and I are off to Amsterdam next week. Hurrah! Think of it as a kind of birthday treat and mini-honeymoon (surely EuroDisney doesn't count?) all rolled into one.

Now we only have three nights there, and so are looking for any recommendations about what to see and do (apart from the obvious, there's no need for innuendo in the comments section now, is there?) from anyone who's been before/recently..
We did find, an internet guide to Amsterdam, which is a good starting point, but now would like some recommendations from friends/colleagues..

Any info would be muchos appreciated..

Am now off to listen to the intro music to "Van Der Valk"