listed on PAprobono.net's web page on "Legal Assistance for Military Personnel Available in Pennsylvania". Rather than have me copy them here, it's better to direct you there, so that when change happens only that web page need be updated.
Active duty service members may wish to go first to Armed Forces Legal Assistance's nice online database to "locate active duty legal activities offering general legal services within the continental United States". A query for the state of Pennsylvania is here
In addition, for those members of the warrior community (servicemembers, veterans and their families) who would prefer to look for their own lawyer, the Findlaw website has a city-by-city list of lawyers interested in representing active-duty military personnel, military reservists, and veterans here.
For LawyersThe Pennsylvania Bar Association has an active Military and Veterans' Affairs Committee. Its efforts include CLE, coordination with some county efforts, the innovative Veterans Court Initiative, and more. See http://www.pabar.org/public/committees/military/
Anyone with more information on these or other programs, please add in a comment below. The purpose is service!