Google doesn't allow keyword advertisements related to political issues -- which is kinda silly, given that these days pretty much everything has a political aspect. I found out about this policy when the Free State Project tried to run a keyword ad using some text I suggested (I think it was something like "Liberty in your lifetime? We're making it happen!"). Google said no can do, that's political. Crazy. Now thanks to Dave Winer I've discovered that Anita Roddick (for whom I used to work, however indirectly, as an employee of The Body Shop) is speaking out against Google's policy. Naturally Google can do whatever it wants (no, Anita, it's not censorship when it's the policy of private company), but if you ask me this policy is awfully short-sighted. BTW, they also forbid any keyword advertising for companies that sell firearms or any products related to firearms. I betcha ESR would be interested to find out about that one. But Google does allow keyword ads that point to sites "containing adult themes" such as "gambling and explicit sexual content". Go figure.