I EDC an ultra tactical OGIO messenger bag. It contains the following:
Heat Source (Laptop): Asus U31 w/10hrs battery life (means I can keep the charger at home, and pack around less weight)
Kindling: Aka, stray homework, assignments and tests that I would more than gladly burn to get a fire started. Or just to burn them actually, doesn't matter why.
Water: My Nalgene bottle. I carry it empty, and fill it up before class so I have something to help keep me awake.
Food: My lunch, so I don't die at work. Its generally some tactical PB sandwiches that keep me going.
Extra clothing: I carry a super stealthy beanie around with me, in case I encounter some bad weather on the 10-15 minute walk home every night. Naturally, its black, and devoid of any marking (so I can't be identified of course).
Sanitation: Some hand cleaner a recruiter gave me, so then I could clean my hands after shaking his hand.
Self defense: I carry a pen. I saw the bourne movies, its now forever a weapon in my mind. That said, it hardly gets used. All my schoolwork is on computers

.
Headphones: Used to successfully ignore the weird breathing patterns of the other people that share my office at work. Works great.
So... yea, I'm a student, but this really is what I carry each day. I also EDC a gerber paraframe, because thats basically the only folder I have. Its pretty sweet, it looses an edge cutting paper, which means I get to practice my sharpening skills

. That said... this setup for SURE works for me day in and day out. In the crazy world of the business school, I've always got what I need, and my pack is way lighter than most peoples bags, which means I feel like I am winning for some reason.
Oh wait... you probably meant going out in the WOODS... Oh, I can't help there.
