I carry a lot a crap, but I've found it all usefull at one point or another.
On my person:
-Wallet
-Notepad & pen
-Sharpie
-Another pen
-HTC Evo
-Calibri lighter
-Wrigley's chewing gum
-StreamLight ProTac 2L
-Leatherman Wave
-Benchmade Mini Griptillian
-Benchmade 710
-Glock 23
-G22 magazine
-S&W 442
-Speed strip with six .38 special rounds
-Keys (w/ USB drive, SwissKey tool, & Energizer LED light)
-Casio watch
-Paracord bracelet
-Ka-Bar Necker
-Repair kit (in an Altoids tin: zip-ties, saftey pins, electrical tape, duck tape, Super Glue, dental floss, tweasers, needle, thread, & other odds and ends that I've found useful)
The GHB bags in the car have a bunch more crap in them and the car itself has typical car emergency stuff. When I was working, my work bag had a little tool kit and a boo boo first aid kit.