Many, many, many. If the GOP increasingly suffers from a suffocating orthodoxy, the libertarian movement (if that's not an oxymoron) is amusingly/alarmingly/pedictably/irrelevently heterodox. As Brian Doherty explains:
Then again, since libertarianism is as much a sensibility as anything else, it's scarcely surprising it should be such a divided house.
UPDATE: Dave Weigel has a characteristically good - and entertaining! - review of "a thrilling and dispiriting year for libertarian politics" under the never-out-of-fashion headline Where Did It All Go Wrong?