Weapons and Armor
That quarterstaff is more than a two-handed bludgeoning weapon. It can be used to push buttons from a distance or to trigger traps. It's also a handy lever. Two of them and a blanket make a stretcher. Use a couple of handfuls of sling bullets in an explosive trap as shrapnel, or roll them down the hall to trip up the party of goblins running your way. You can use a breastplate as a sled.
Mundane Items
You can use oil to create an oil slick, similar to the "Grease" spell, to slow or trip up your enemies. Used with a fire spell or flame arrow, it can wreak havoc. Torches can be used as clubs, possibly adding fire damage if they are lighted. Blankets can be used to put out fires, carry things or be torn into pieces for bandages. In a pinch, you can braid strips together to make a rope.
Food
A handful of pepper blown into the face of an enemy or a shot of lemon juice to the eyes can temporarily blind him. A trail of breadcrumbs can get you back to the entrance or lure some monsters into your trap. You can also use food to catch animals to be trained as pets or familiars. You can use salt to torture a wounded enemy. Liquor of any type can be used to make improvised firebombs.
Gold
At some point, you will end up with more money than you could ever spend. Your gold is not useless, however. Use a bag of gold as weight in a weight and pulley system or to sink something to the bottom of a lake. Throw a handful of gold at that oncoming horde of orcs and run while they are distracted by the shiny projectiles. Use gold pieces to reflect light as a signal.