Unitarian churches have a
free pulpit and
free pews:
There are two time honored institutions in Unitarian Universalist churches that are, or should be, guarded by clergy and laity as if they were the Holy Grail. They are the free pulpit and the free pew. Succinctly stated, the free pulpit means that when a congregation lends its pulpit to a minister by calling that minister as its spiritual leader, the congregation pledges complete and unencumbered freedom of speech to say anything from that pulpit that he or she believes to be true. But that freedom is not something the preacher is born with, but originates in the bond of affection, the covenant established between the congregation and the minister. The free pew means that when a Unitarian Universalist congregation is gathered by a bond of affection, a covenant that makes it into a spiritual community, the most sacred agreement made is that no theological test will be given for membership in that congregation.
A number of churches and ministers put their sermons and addresses online - it's a fantastic spiritual resource and a way to understand Unitarianism better.