I too do the “check my zipper” thing; usually whenever I get out of the car or before I enter a building. I don’t know why. It’s always up.
I also make sure my keys are in my pocket when I cross a grating.
When I eat fried eggs, I must carefully cut and eat the whites first, then pop the whole unbroken yolk into my mouth.
Hurrah! What do I win?
Oh, and I can’t wear matching socks… they have to be odd. 
When I go up or down stairs or steps they must be divisible by four. If it takes me eleven steps to go up some stairs, I have to go back down. Then I go back up again skipping three, which leaves eight. If there is only two steps I must go up them twice.
Yep, I’m as crazy as a shithouse rat.
If I wear nice clothes to work (which I don’t have to all the time) when I get home I must change into non-work clothes immediately. If I don’t I feel like they’re getting extra dirty by my wearing them longer than I have to. (I went to private school, so that’s probably where that comes from.)
Earrings freak me out. especially big dangly ones. ick. and stuff with pearls on it. actually, jewelry in general. But not regular watches.
When I’m driving with someone my eyes never leave the road even when we’re talking. Never, ever. I have a feeling in the back of my mind that if I stop watching the road for any reason, then that will be exactly when we die in a firey CHiPs accident. Paranoid, but I figure good paranoid. Some people get offended by this, though. 
Each 1 thing at a time, moving clockwise around the plate (I actually turn the plate) My brother does the same, but counter-clockwise.
When eating pancakes, I must eat the sides, clock-wise, saving the middle, butteryiest bit for last.
And there will be no bras or shoes in heaven, which is why I must take both off as soon as it is decent to do so.
Not EACH but Eat
<<sigh>>
When I’m cleaning my teeth, I always have to do it a certain way (bottom right section, top right section, bottom left, top left, bottom front and top front!), and if for some reason I get disturbed and lose track of where I was, I have to start all over again.
When I pack my handbag before I leave the house, I alway mutter “purse, fags (cigarettes), phone, keys” - can’t leave the house unless I’ve done this.
Oh, and I always have to check the forums on the Straight Dope in the same order each time - starting with the Pit, or I feel strangely unsettled!
I sit with at least one leg tucked under me. Right now in the desk chair I sit ‘Indian style’.
It absolutly drives me bonkers that the household members don’t rinse those damn dishes. Grrrrrrrrrrrr
I obessivly put office supplies in the desk drawer.(Unfortunatly, what I need still isn’t there)
I must have my keys attached to me by a clip and/or safety pin. I have only one key, but both of these on my ring.
If I step out of the house, and must take a trip in the car or bus, I carry a book. I feel exposed without one.
Me too! Except I leave the fags out of it. It’s wallet, keys, cell phone, lighter, ** cigarettes **.
I don’t know if this counts, but I’m not very observant. If I decide to clean off a counter, I’ll concentrate on each item and decide if it’s trash or not. I mean stare like an idiot at each item. I will collect all the ones that I determine are trash and throw them away. Go to another part of the room, pass by and I’ve left 3 or 4 ‘trash’ items. Damn it.
Also, I have been in my current house for 3 years. I cut the grass the first week I was there and after that decided it was worth the $20 for the kid down the street to do it. Well, for the first time in 2+ years, I had to cut it myself. As I was making passes on the side yard, I got to the point where I had to start going around the tree. It’s at this point I stopped in my tracks. That tree was fucking huge. The last time I noticed it was maybe at 10 ft? It had to be 40 ft high. I pass by it every day and never notice it.
Oh, and I can’t go to sleep without the bathroom fan running.
And if you MUST put the toilet paper on the roll, the end must roll toward you on the top/front, not drape from the back/bottom.
I can’t stand to drink bottled/canned beer without a coozie(?). I believe all the cold freshness is seeping out into my hands.
The sheets have to be tucked in at the bottom of the bed and they cannot come out.
The clock cannot face me in the dark of night. It’s evil red light keeps me awake.
I start with the Pit and move my way all the way up to GQ, skipping Cafe Society cuz it’s not really my cup of oolong.
My mp3s are all organized Genre – Artist - Name of Song. The ID3 tags must be Artist - Name of Song. If there is anything wrong with the song, one bleep, one bloop, one skip, it gets deleted. There must be capitalization. If I see a song incorrectly named, it must be fixed on the spot. Oh yeah, and I can’t stand to have anything in the Recycling Bin, the Recently Used Documents list, or the History. I turned off AutoComplete on everything where it was practical to do so. Except for Microsoft Word; sometimes I like it when it realizes I’m typing my name and offers to insert it automatically.
I also find it damn near impossible to let people use my computer, particularly if I’m not around. I’m just convinced that the moment I let other people start using my computer, bad things will happen to it. I feel vindicated now, since my roommate broke a disk in there while I wasn’t around, and he’s also the only person for whom the computer has spontaneously turned off. Anybody else who has used it used it while I was around.
Man… I’m a freak.
(shakes head)
And its evil red light makes me use contractions where they shouldn’t be.