I live in amsterdam and often find it difficult finding a climbing partner for those indoor sessions. (or outdoors for that matter)
I've gotten to know quite a few people in the same boat so I created a social network site for us all to keep in touch and for us to search for available partners.
If you sometimes find yourself stuck for a partner for some vertical fun then join up / take a look and never be stuck again.
http://amsterdamclimbers.ning.com/
Dan.