Free shipping if user meets conditions

[TC24601]

Hi,
We're looking for a way to offer promotions to customers when the user has met certain conditions; for instance, while ever the customer is subscribed to the newsletter they would get free shipping, and lose it when unsubscribing. We've looked at a few extensions that achieve this though coupon codes, but that then limits our ability to use coupon codes for other campaigns.
Any suggestions would be appreciated.

[theMageComp]

Here are few real world promotional discount rules you can create for your store.   

http://www.demacmedia.com/magento-commerce/10-real-world-examples-of-shopping-cart-price-rules/

Moreover, We are also developing one custom extension for First delivery FREE, we will update you once it is ready.