I do have a bag which contains most of what you describe. It's an older version of this LL Bean bag: http://www.llbean.com/llb/shop/34014...-accessory-bag
In it, among other things, are a bright 2AA LED flashlight, a Leatherman Juice S2 multitool, a 6-in-1 screwdriver, pens, a notepad, a small first aid kit, a small digital video camera.
I don't carry ammo in it since I take this to work with me every day and I'm never armed at work.
I don't know quite when the concept of a briefcase turned into an "EDC bag" but essentially I've always carried similar stuff with me. It just used to be in a hard-sided briefcase but now it's in a soft-sided nylon bag.
If you're interested in all the tools and gizmos that make up EDC, there's a great forum: www.edcforums.com
, that has active discussion areas for everything you can think of that you might think about carrying.