I have a very cool Flash based shopping cart widget already created and hosted on my own website. The backened.. payment processing etc/database are ALL handled by the company that made the widget.
An EXPERIENCED Facebook apps or PHP developer to help me install that widget as a Facebook Application. Users who install it will be able to see that small window where they can buy inside it without leaving FB.
Again this is just script installation.. and shouldnt take more than a couple of hours!
More details upon request.