It's been a while since I've had any trolls, but I feel like spelling out my comment policy anyway, possibly in hopes of attracting some.
1. Anonymous comments will be deleted. Choose the "other," "open ID," or whatever else may be available if you don't have a blogger account. Use a name of some kind so that I don't have to deal with confusing multiple anonnies.
2. Commercial spam: If all you're doing is posting a link to your naughty pills, say goodbye to your comment. If you're posting a relevant comment but include a commercial link to something irrelevant, you're at risk. If you're posting a link to a funny product that echoes a point being made, you're safe.
3. Consequences of bannination: So far, I've only got one person 'banned', but I let him post for at least a month or two past that, with only some of his posts being deleted, mostly involving pointless repetition of points already refuted in the main posts and massive copy-paste. The rest got through. The reason: He did a spectacular job of making himself look worse. So, if you're banned, and I don't delete your posts, you may want to start thinking before you type, because your posts are staying up for a reason.
4. Flooding: Please keep your posts to a reasonable length. I don't want to see a massive copy-paste job, especially if it's irrelevant. There are these little things called 'links' that a person can click on to see stuff. No need to bring the crap over here. I'll even tell you how to make them: [a href="http://www.whatever.com/"]Link text[/a]. Just replace the brackets with greater/less than signs.
5. Off-topic stuff: Please stay on topic. If you're a detractor, please remain relevant. Psychoanalysis of me to the point of hypothesizing that I wasn't petted enough as a pup because I doubt astrology is quite irrelevant, not to mention fallacious. I confess I do my own bit of psychobabble on occasion, mostly to show the counterpoint: Most of the things I see woos accusing skeptics of are, more often than not, properties the accusing woo possesses.
6. Using all caps or more than three exclamation points on a sentence automatically takes away any chance you had at being taken seriously. To get back there, you need to go back to your indoor voice, and use proper grammar for an extended duration.