The John Birch Society sounds saner than Hollywood and Washington combined. Not that that would take a whole lot of effort, mind you.
Although the John Birch Society advocates a limited, Constitutionalist federal government, as does the Tea Party, there are significant differences. The Birchers believe that American politics are dominated by a "master conspiracy" centered in the Council on Foreign Relations, a New York-based think tank, a notion rejected by most conservatives.
The JBS has also been cool toward issues and personalities that excite conservatives. They wouldn't support Ronald Reagan, apparently because he held some liberal views back in the 1940's, and they were opposed to aiding the Nicaraguan Contras who fought against the Communist Sandinistas. They even opposed Proposition 13, California's tax limitation initiative that all other conservatives in the state enthusiastically supported.
And unlike the loosely-structured Tea Party, the JBS is monolithic. Its leadership is not chosen by its members; it is run more like a business. Members belong to local chapters whose chairmen are chosen by the Society's leadership and not elected by the members, and there is a Home Chapter for those not members of local chapters.
So to compare the Tea Party tot he JBS is to ignore some important differences.