Amtrak is an affordable, appealing option for many Unitarian Universalists coming from out of town to Providence for General Assembly.
The tickets become much more expensive if you buy them within 21 days of travel. Other discounts exists, but it's hard to be the convenience of a single passenger travelling. Companion fares which could be booked later really don't see you that much by comparison. So get your tickets now.
Use this tool to find the cheapest tickets from your location to Providence.