HACKISH CONSERVATIVE THINK TANKS: I agree with Ezra that Heritage is the most hackish of the Big Three conservative think tanks in Washington (AEI has some non-ideologues and Cato is honest about how ideological they are.) But I think it should be added that outside Washington reside some pretty shameful rightwing think tanks as well. Consider, for instance, the California-based Hoover Institution, which has "scholars" like Peter Schweizer, author of Do as I Say (Not as I Do): Profiles in Liberal Hypocrisy. This intellectually incoherent smear job on the personal lives of predictable targets like Michael Moore and Barbara Streisand has zero value in terms of policy analysis.
Meanwhile, as I've written before on TAPPED, City Journal, the publication of the neo-conservative Manhattan Institute, shamelessly flacks for Giuliani's presidential candidacy (if my organization did anything like that we'd lose our tax status in a heartbeat.)
These kinds or organizations may not be perceived as influential within Washington (they don't have a roster of former Reagan and Bush officials working for them and so forth.) But books like Schweizer's influence the public debate (I once debated him about it on an NPR affiliate), and giving him the imprinteur of a think tank allows him to be taken more seriously than he deserves. And the Manhattan Institute, as Giuliani's house organ, had a lot of influence on local public policy during his administration. Perhaphs its time for someone to start an organization that systematically rebuts the nonensense spewed by rightwing think tanks, as a complement to what Media Matters does to FOX News and rightwing talk radio.