I always make sure I have just a few essentials, even when running up to the store.
Watch (Marathon GSAR)
Wallet (always have about $50-100 cash, Driver's License, Mil-ID and CHL)
Oakley Half-Jacket's
Folding knife (or two)
SAK (either an Outrider or most likely a SAK Farmer)
Burt's Bees chapstick
Cell Phone
LED Flashlight (Fenix, Surefire or Novatac)
Compact "Space" pen
Small peanut lighter, Mini-Bic or small Windmill butane lighter
Depending on what I'm wearing (usually something with cargo pockets), I'll add:
550-cord; about 4-6 feet braided, at least one hank sometimes two
Small flat role of 100mph tape (aka duct-tape), usually about 6-10 feet
Folded cravat/bandana
I have a few small (about the size of two stacked quarters) dental floss tin dispensers that hold about 10 meters of dental floss. Another small item that has multiple uses. I do have a very small, flat PSK/FAK that has a few bandaids, moleskin, needles and safety pins, but unless I have cargo pockets, it's usually in the vehicle/daypack and not a true EDC...(I need to fix that though).
I always try to carry a fixed blade (I carry a 5" bladed Mad Dog PATAK for duty), even if it's a small Fallkniven WM-1 (in a MercHarness) or a Gossman PSK.
Additionally, I will aways have a CCW if I can legally carry it where I go; as big as my Bobtail .45 or more compact such as my S&W Centennial .38 or Kel-Tech P32....my EDC for hikes is a Glock 23 in .40SW or my newly aquired Charter Bulldog in .44 SPL.
The key-chain always has a few EDC items...
Whistle
Mini-Prybar
Photon LED
Nail clippers
Sliver Grippers (should be carried by everyone!)
Utilikey
If I'm packing a belt-mounted multitool, I really like the Leatherman belt pouches as I can get a small DMT sharpener, AAA LED and a small Ferro-rod in the accessory pouches as well:
Don't forget a good pair of walking/hiking shoes or boots, a decent pull-over and/or windbreaker and I usually have a good pair of gloves and hat within reach.
ROCK6