Dr. John Ray, an Australian fellow who may be the most prolific blogger working now (five blogs and counting, if I'm not mistaken), uses this forum to examine leftism and deconstruct it. He believes leftism is a psychological disorder. You may or may not agree with him, but you'll appreciate that he is going about proving his theory in a scholarly fashion. Check his other blogs (PC Watch, Greenie Watch, Gun Watch, and Education Watch) as well.
I posit that ideological excess reduces one's ability to put forth ideas. In that sense, Ray is doing liberals a favor with his work.