bottle of water
water for not being thirsty
empty bottle for later storage maybe
you could have more water or another liquid
or maybe store pebbles.
who doesn't want a bottle full of pebbles for when the time for self defense?
get down on the attacker muslim-style.
stone that motherforgeter.
you could also store some nice sweets to share with your friends or eat them all yourself if you're fat and/or selfish