I’m with Beadalin on the American regional accents thing. Total turn-off.
Topping the “unpleasant” list are New York and New Jersey accents, closely followed by Midwestern and Baltimore.
Non-American accents don’t do too much for me either, especially English, Irish or Scottish. Man, I hear them and I just want to crack up!
Not single anymore, but I remember the fastest way to not get my number was to be an older man. Not even by one year. Just didn’t trust them. Plus I always ran into the ones that thought I should be impressed by them insulting my intellegence. How is that cute?
BTW Bartman is 2 years younger than me. Try it. You’ll like it.
Well, this is purely a theoretical exercise at this point, but…
Bad teeth is definitely out.
The inability to have a conversation without inserting “you know” every few seconds…ecch.
Not liking the movie “The Princess Bride” would an instant DQ in my book.
I’m sure there are more, but I haven’t had to think about this in a while, so…
[flirt]BTW, Arden, I’ve got hair down to my waist and I wash it every day…sometimes twice!![/flirt]
[sub]I’m not stalking you. I swear.[/sub] 
My biggest turn off has to be tatoos and body piercings…
A woman can have the most perfect body in the world, but it will look completely ruined to me if she has a tatoo or some kind of piercing that is anywhere but her ears.
Even small tatoos on the ankle and navel piercings are enough to turn me completely off. 
Wow- I chew ice with alarming regularity. I’ll take that to mean I should have far more sex than I currently am (and you won’t see me complaining).
Now, for a list of petty, piddling, paltry, picayune, piffling, puny, pointless turn-offs…
Bad breath. I don’t mean garlic breath after an Italian meal, or morning breath, but rancid, awful, horrible halitosis that makes me want to turn away in disgust. I understand for some people it’s a medical condition, but there are ways to minimize said breath. If you can’t, I feel sorry for you, but your mouth will come nowhere near mine.
Bad teeth. Not just crooked teeth, but dentist-book-of-horrors teeth. (Austin Powers qualifies, as mentioned above.)
Willful ignorance and superstition.
Thick Southern accents.
…and that’s leaving out a lot of the conditions.
If you have lots of pets, you will not get me.
If you call then “my children”, ywngm.
If you talk to them in baby talk, ywngm.
If you whisper to other people (cupped hand over ear stuff) when I’m around, ywngm.
If you EVER say “should have went”, ywngm.
If you confuse “good” and “well”, ywngm. (Though I am forgiving on this one.)
If your prized possession is your car, ywngm.
If you listen to one type of music only, ywngm.
If you are currently married to someone else, regardless of the situation, ywngm. (Is this a personality trait?)
(all of these are above and beyond others listed previously.)
Of course, Mrs. Spritle got me and now nobody else can.
Hiydoin’, hon, juse mean dayun-tayun Balmore ors moreslike sauwth side nears Essex n Dundawk? Mebbe GlemBurnie or somethink?
The most petty of all my deal-breakers in chronological order…
(These have each lead to a break up)
talking during a movie
being lip-less
not understanding a movie plot
uni-brow (why should women be the only ones to invest in tweezers)
Pronounced nervous tics.
Excessive bodily awkwardness.
Cases of general uptight-ness.
Ridiculous laughs and unpleasant-sounding voices.
Dislike of classical music, and music in general.
Ditto to the ear wax and limp handshakes.
Eeeeww!!! Yes! Don’t be a fop. Grab my hand and give it a nice firm shake.
Good call!
People who like grapefruit…
People who are indecisive about choosing music…
and, of course,
People who show up at their first meeting with someone drunk.
Wait…