Dear ... 
I appreciate the time you recently took to discuss with me, the position of __(name of position)__ that you currently have available at __(name of organization)___.  It was a pleasure speaking with you and learning more about your organization. 
I meant to mention during the interview, that I know how important __(describe something important to the organization)__ is, and I wanted to make sure you knew that I am extremely well versed in __(type of skill required to do it)__.  I share your company philosophy and believe that I would fit in nicely to your environment. 
I believe that my background and experience would enable me to make a strong contribution to the efforts of your team.  In addition to my technical skills, I will bring enthusiasm and the ability to work well in a team atmosphere. 
Thank you for the chance to discuss my qualifications with you.  I look forward to an opportunity to visit and speak to you further about the possibility of joining your team. 
Sincerely,