any reference books you can think of
surgical gloves
one way CPR mask
garbage bags
paper sacks for evidence collection
fire extinguisher
flex cuffs
rain gear
antiacids (if you are prone to heart burn)
Do you wear contacts? If so a lens case and saline and either a pair of glasses or extra pair of lenses
Do you carry OC? If so a decontamination source.
let me think a while, I will get more ideas
"Speed is fine, but accuracy is final" --Bill Jordan
Remember those who died, remember those who killed them.