Seth Godin's article, "Too much free" (http://sethgodin.typepad.com/seths_blog/2009/05/too-much-free.html), had me nodding in agreement with the fact that sticking FREE on a product no longer garners the attention it once commanded. On releasing PoP Project (http://paradigmpop.com/pop-project) we took a long time to decide to allow a free trial, and our final decision to allow it was not so we get more users. Rather, the free trial was rightly suggested by one of our private beta customers as a period where the customer learns how much value PoP Project brings to their project. That company was running PoP Project for a few weeks and at that time were aware of how 'on-track' macro level hand holding in PoP Project pushed their project along. After this grace period, they were ready to pay for the service because they knew it brought them value.
We need people to understand the value PoP Project brings before we ask them to pay for it. That is why we have it free for the first month right now. I am proud to say that once half of that free trial is over, most of them find so much value that $12 a month seems almost, well, free.