The Telegraaf webshop has a special offer, where you can order tickets valid for 15 euros, for a complete day in Amsterdam, which includes 5 different attractions
This sounds like a good deal to me if the following attractions are of interest to you:
- Foam fotography museum
- Heineken experience
- City tour Amsterdam
- Museum Het Schip
- Lovers Craft & History Canal Cruise
Valid until 31/12/2012 (foto museum until 31/10) and you can pay with Ideal (dutch online banking), visacard and mastercard. It seems to me that you need to do all in one day but I am not sure.