The Dampkring is great, for anyone going there is some unspoken rules for smoking over there. its all joints, really not that may pipes or bongs. also, only smoking in participating coffee shops is accepted. look for a green and white flag on the window. lastly, if you go to a place to smoke, either buy weed there or buy coffee or tea, dont just go in to smoke some stuff you brought in.
and the heineken is great over there...definately do the brewery tour.
the reijks museum is also there, but i think its under construction until 2008. there is a sex museum by the main train station that was decent to go to, and of course go to the van gogh museum if thats your bag.