Wow. I’d probably be absolutely reviled if many of the posters here met me in person. I fall under so many of the categories expressed in this thread…
I buy hardcover books exclusively, and will always pass on a softcover, even if it’s something I really want to read. I have every book I’ve ever owned since the Ninth grade. I never loan my books to anyone, nor will I ever throw away, sell, or trade one.
I can’t stand cats. I’m not in love with dogs either, but I absolutely despise cats. They creep me the heck out.
I’ve never had a drink in my life, not for religious reasons since I’m anti-religion. I just never had the desire. Since I’ve gotten a little older I just don’t see the need to start. . .plus the stuff smells really bad, especially beer, which has a kind of uriney odor to me.
I’m married to my job . . .well, that’s what my wife says anyway.
I don’t think much about my predjudices, until threads like this are born 
I’m a morning person. . .not because I necessarily want to be. It’s just that over the years I’ve realized my day simply works out better if I’m up at the crackety-crack of dawn.
I wear glasses and prefer them over contact lenses. My wife believes I look adorable without my glasses. . .I believe she’s delusional.
I don’t like to shoot guns. I went hunting in Anchorage with my dad twice. Tried it, didn’t like it. Hey, I gave it a shot. 
I’ve never changed the oil in any of my cars in my life, have no idea how to do it, and have no interest in acquiring that tidbit of knowledge.
I went to NYU, and yes, I consider myself reasonably bright, though in the interest of full disclosure I must admit to being a bit artsy. 
My predjudices. . .
I believe people with more than 3 cats are mentally unstable, and probably filthy. Their level of filth increases exponentially, in my assessment, with each additional cat over 5. I would never willingly enter the home of someone with more than 3 cats.
I have a tendency to consider those who are religious, especially Christians, to be somewhat less than optimally intelligent. If, during the course of conversation, someone begins to quote biblical scripture, whether in response to a query or as a counter during a dispute, I mentally dismiss them and find it difficult to mask my disdain from that point.
I find people who don’t read for the sheer enjoyment of it a bit odd.
Smokers. I mean, come on. it’s 2006 for goodness’ sake.
Science fiction enthusiasts who have no idea who Hari Seldon is.
I’ll jump on the bandwagon of those who believe BMW owners are pretentious wannabes. I’m embarrassed for them, since it seems they don’t have the sense to be for themselves.
Tattoos on women. Blech! I asked before and I’ll ask again. . .aren’t tattoos done at this point? I mentally reduce a woman’s potential IQ by five points for every epidermis-saturating ink splotch she sports.
I believe people who get their perspective on world and national events from FOX News should be kept away from sharp objects and prohibited from bearing children.
Nascar. 'nuff said.
Women who have banged their feet up through years of abuse by wearing shoes that don’t fit, or fit poorly, yet insist on displaying those gnarled monstrosities in public by wearing sandals and flip-flops. I’m not against women’s feet. I just don’t like having my eyes drawn to a living Picasso with candy apple-red painted toenails.
I am utterly disgusted by people who discriminate against anyone because of race or sexual orientation.
People who don’t believe racial discrimination exists and is still commonly practiced in the US make me sick.
People who believe women should be forced to bear children against their wills should be locked up and never released.
People who want to force women to bear children, even if doing so endangers their lives, should themselves be put to death.
I believe the Promise Keepers are a bunch of patriarchal whackos with brainwashed, Stepfordite wives.
Dittoheads.
ID Proponents/Creationists/YECs. I actually put YECs in the “I’m stupid and proud of it” category, along with adherents of astrology and psychics.
Men with ‘short man’ complex. . .only because I’ve had a few too many unpleasant experiences with these insecure, overcompensatory weasels.
People who derive joy from others’ pain or discomfort.
People who refuse to admit when they’re wrong.
Anyone who justifies any aspect of the Iraq war.
Bush apologists