It would help if you give some idea of what interests you. Art history? Head shops? Boat or bike tours?<p><a href="http://www.tripadvisor.com/Attractions-g188590-Activities-Amsterdam_North_Holland_Province.html" rel="nofollow">http://www.tripadvisor.com/Attractions-g188590-Activities-Am...</a> lists 571 things to do/see/visit. Brouwerij 't IJ, which st3fan recommends, is #20 on the list.<p>Or is it that you would prefer something which isn't on that list? There's no Ruby or Python user group meeting, but picking a programming meetup for next week at semi-random there's <a href="http://www.meetup.com/Creative-Coding-Amsterdam/events/223837968/" rel="nofollow">http://www.meetup.com/Creative-Coding-Amsterdam/events/22383...</a> .
If you are into smoking, visit the coffee shops, at least a few, and take a long walk while smoking. It is psychologically freeing (I prefer smoking to drinking personally). Relax and talk to others.<p>Take that long walk either way and look at the wimsy on the buildings. Many have something a bit off. If you are into art, go and look at some classic stuff. Walk through the red light district if you've not seen one. Be careful of the trams and learn to listen for bicycle bells. If it is summer, walk through a street fair area, buy something ridiculous (I'm now the proud owner of a gas mask). Look at the funny apartment numbers.<p>Enjoy muchly :)
Do you like tasty beers? <a href="http://www.brouwerijhetij.nl" rel="nofollow">http://www.brouwerijhetij.nl</a><p>It is a wonderful little brewery with a great view:<p><a href="http://mikestravelguide.com/wp-content/uploads/2013/08/Ij-Brewery-Amsterdam-and-Gooyer-Windmill.jpg" rel="nofollow">http://mikestravelguide.com/wp-content/uploads/2013/08/Ij-Br...</a>
Make sure to visit something outside Amsterdam as well. Scheveningen, keukenhof, volendam, giethoorn, utrecht and haarlem are all within short distance and worth visiting.
If you are into (hacking | making | DIYbio) consider a visit to Waag <a href="http://waag.org/en" rel="nofollow">http://waag.org/en</a>