I think certain aspects of the Crusades, the Inquisition, the Reformation and today's co-opting of the faithful by Alinsky-style organizations like the IAF or "Interfaith" (much less the feds' "faith-based funding" enticements) speak for themselves.
I'm also working on a post concerning Medjugorje which I'll add to that list.
Additionally, as a Catholic, I'd add the likes of certain clerics and so-called theologians within the Catholic Church who've bastardized their offices to promote purely secular and political objectives: like the Roosevelt-era politico Cardinal Spellman and Monsignor McHugh where human life was concerned; the eco-feminists of WomanChurch; that "rainbow" sash group of homosexuals ... anyone who refuses to leave the Catholic Church but, rather, uses the Church's infrastructure and preys on trusting parishioners who'll be cowed into conforming with this or that agenda to change the liturgy, desacralize the church, neuter the Word or promote supremely politicized "social justice" ... Chavez lettuce boycotts, Brasilian land movement, empowerment of women and such.
I guess to that list must be added the legions of former religious who -- while not abandoning the Church -- have totally perverted their faith by opting to engage in "ministries" wherein they promote New Age concepts such as the Cosmic Walk and support the marxist agenda ... whether heading in droves to Latin America or protesting outside Ma Benning's school for boys.
If I concentrate primarily on Catholics, please understand that I feel the specter of monied evangelizers preaching "prosperity" as God's ultimate blessing and eschewing all manner of suffering as some sort of curse (when, in truth, the opposite's generally the case) speaks for itself.
Thanks for the clarity, we are in agreement, I would include bishop spong in this group, still this groups crime is one of heresy against the church, islams cirmes seem to be against all humanity and stand out accordingly.