Message boards are usually thought of as a way to post queries and respond to queries posted by others. Some message boards, however, allow you to post transcribed documents such as wills or obituaries. And there are even some that allow you to post images -- photographs and scanned documents. One advantage that a message board has over mailing lists is that old 'conversations' remain easily accessible. 

GenForum, a part of the Community area at Genealogy.com, offers free message board and chat services to online genealogists.

Yahoo! Groups provide not only message boards, but a facility to exchange files and photos. See the index of Alabama Genealogy Groups.