Since I walk 97% of the time, and my club has coolers of water bottles strategically located around the course, I always have a couple of bottles of water in the bag.
And, a can of Copenhagen snuff - yes, I know how bad it is for me, hope to kick the habit this winter.

In addition to the usual tees, balls, divot repair tool, ball marker “coin”, black sharpie, and gloves, I have a valuables pouch that contains these items: finger nail clippers, pair of contact lenses, two cleats, pocket knife, small bottle of ibuprofen, back-up rangefinder battery, spare ball marker, spare divot repair tool, several different sized band aids, bee sting ointment medicated pads, pencil with an eraser, several toothpicks, a bottle opener, a small mirror (to help with contact lense problems), and a small Swiss Army knife.