Mike,
I carry a two way radio, so that I can be in contact with the guys I hunt with.
Also in my pack I carry the following items:
Compass
Water
small flashlight(2 AA mag lite)
Matches in waterproff container
two kinds of fire starter
lighter
small first aid kit
Space blanket
extra knife & folding saw(also handy to use on game)
extra gloves(if in cold weather)
25Ft of parachute cord(wrapped around a glow stick)
and a energy snack