Earlier, I mentioned the possibility of a Universalist church outside the UUA. As it happens, there are several, though not nearly as many (who opted out of joining the UUA) as there once were. Some died; some became Community Churches and lost their Universalist identity.
One of the survivors -- Universalist and Christian, and dear to me -- is Rockwell Universalist Church, Winder, Georgia.
Some -- well, so far, one -- Unitarian church(es) are in the American Unitarian Conference while an case for independence is made by the [2009. defunt, www.utahunitarian.org] Wasatch Front Unitarian Fellowship "an Independent Unitarian Presence in Utah"
Some Unitarian Universalist congregations, especially out west, seem to have a relationship with a UUA district, but aren't members of the UUA. Whether these small groups ever plan to join the UUA is unclear. I've put the names of a couple (with membership numbers in parentheses) in the extended entry.
Wickenburg, Arizona: Unitarian Universalists of Wickenburg (30)
Las Vegas, Nevada: UU Community of Southern Nevada (16)