I've been commuting to NYC for a long time now - I used to live in Manhattan, but moved way the hell out to the country in 1996, and have been commuting in fairly regularly ever since.
Last week, I came home as I usually do, and I decided to empty out the computer backpack and make sure some of the cold-weather additions (hand warmers, extra hat & gloves) were all there.
It's amazing how routine degrades into complacency, and how that leads to a a lack of preparedness.

- The battery in my Ham Radio HT was nearly dead
- I had no AA batteries in my bag at all! Not a ONE!
- The one FLASHLIGHT I had in my bad was a fantastic Coast brand light, the batteries were fine, but as I remembered later, it was that goofy "N" cell light, not a proper AA or AAA light. That's gotta go.
- I had only a .5 liter bottle of water on board
- My FAK was missing a few supplies (see my other post for that)

So, all in all, not a total disaster, but it was a reminder that it's a constant need to make sure what you carry is actually ready to go.

Yeah, the best way to remember to check gear is to do it on a regular basis. Perhaps every first of the month?

TRO

Its easy to get that way with so many things to do. I used to have reminders popup in my calendar/pim system and they would almost always get snoozed because I was doing something else at the time. So near the end of last year I sat down and made a spreadsheet of gear maintenance so I can sit down when I get time and look at everything that needs done. Things like checking batteries once a month or checking the vehicle kits every spring and fall, etc.

Yep, I've caught myself once or twice thinking I had something in EDC that I later discovered wasn't (never more than inconvenient thankfully). I've since taken to pouring over the contents on a regular basis. Sometimes I may even get a bit obsessive about it, looking to others as Gollem fondling his precious ring.

Speaking of complacency, it is absolutely astonishing to me how the gen pub seems so nonchalant about public activities. Forget the crime rate; after spending time in Iraq my radar is always on when excurting around metropolitan areas especially. I reckon my best EDC has to be my attitude now. I find myself continuously evaluating the surroundings for potential threats as well as possible innovations in a pinch. Funny how a few bombs and getting shot at will do that to a person. There were an awful lot of folks that went to Iraq and weren't up to the reality of it and caught the next plane home to their secure little fantasy world.

One thing I do, particularly for my FAK, is put a piece of tape on it, & write the date. Every year, on that date, I change out the meds. Inspect all the packages of everything else.
Batteries I change nearly monthly on GPS, flashlights, etc, because they get used so frequently.
I have a 4 mile commute (jealous, huh), with a fairly straight drive the whole way. My major concern is normally me hitting a deer at 6 AM. Which, I can simply wander to the nearest house, and barter food for assistance <img src="/images/graemlins/wink.gif" alt="" />

Slacker <img src="/images/graemlins/grin.gif" alt="" />
My bus leaves at 5:30 AM! And we live in the state with the highest incidence of car-deer strikes in the USA. Woo-Hoo! We're #1 We're #1 We're # 1....

Seriously, tho, the early morning crowd out here is pretty amazing. The bagel and coffee shop opens at 4:30 AM, the gas stations open at 5:30 AM.

I think I wouldn't be upset if it's based just on the specific items you mentioned:

Ham radio HT: who are you going to talk to over it anyway? A cell phone with SMS is probably more useful.

AA batteries: why carry them if you have nothing that uses them? Anyway they're the easiest battery size to scrounge.

Flashlight: Stick a bunch of 50 cent Photon II clones ("Fauxtons") in the bag. Really, in an environment like NYC you don't need a powerful flashlight, you just want one that can light your way around a dark space.

.5 liters water: how much water are you reasonably going to EDC anyway? I'd say put a few 1 liter freezer-type ziploc bags in your kit, they are good for carrying water with just the slightest bit of extra care compared with real waterbottles. The 1 gallon bags are good too, but more unwieldy so they need more attention. The new ones with the sliding zipper-like seal leak water a little bit at the very corner (tolerable if you're just carrying a bag or two from one place to another). The old press-seal type don't leak at all.

FAK: yes you do need to address that.

I agree with the Ham radio and batery remarks but I disagree with the water advice for a few reasons.

1. Getting water sometimes is easier said than done. 1/2 liter isn't that much and will keep you going until you can find or secure more water.
2. In an emergency all water should be considered contaminated. If your not carring a micro-filter or Chlorine dioxide tabs your looking at boiling water. As most people don't carry microfilters, boiling and purification tabs are your only real opitions and they require time until you can drink anything.
3. Zip lock bags are great (I have 2 quart sized bags in PSK) but they only go so far. Having a real bottle can be a major plus if you've got the room to carry it.

Hope you don't take offence to my comments as that is not my intent, esp since I'm a new guy.

Yes carry some purification tabs for sure. Could add: Platypus bottle(s) as an alternative to a full sized waterbottle. While less durable than lexan bottles they are much tougher than ziploc bags. They come in sizes up to 6 liters. They are collapsable and the larger ones roll up.

Should add: I just reviewed the Countycomm SOLED clip light in the campfire section -- check it out. I really like the little light, a handsfree light that weighs just 15 grams. Very functional headlamp if you have a baseball cap, but usable just clipped to your jacket collar or to your eyeglass frame if you wear glasses.

One problem with the theory of carrying water purification tablets- they don't do squat with chemical contamination. From a clean water point of view, major metropolkitian areas might as well be deserts if there is no water. All you have that you can trust is what you have with you when things go sour.