I am sorry if these items/ideas were already suggested in the previous 10 pages. I scanned them and didn't see them so here goes:
1- Construction Materials - Sandbags - Craftable with sand and cloth and a high probability of finding at army camps.
2- Weapons - Flare gun - Ammo crafted with Cloth make a Parachute flare lighting areas at night for a short duration. Also can light zombies on fire.
3- Defensive weapons - Heavy Machine Gun turret - Crafted with 2 AK-47s - Eats ammo like the SMG turret but puts out twin 7.62 destruction.
4- Resources - Fruit Trees- Harvestable Fruit from trees that remain for several harvests before dying and needing to be cut down and replaced.