Jeff Schertz does a fantastic job of explaining the ins and outs of configuring Common Area Phones for Lync. Everything from the quick and dirty way of getting them going through to a comprehensive run down of creating new PIN policies and client policies for a larger deployment.

This information came in super handy for me when I needed to know details on how to get CAPs working.

Read his post here: http://blog.schertz.name/2011/04/common-area-phone-configuration-in-lync/