Spatulas are probably pretty deadly
Not plastic spatulas obviously (unless you sharpen the handle into a nasty spike to shiv somebody with) but the metal spatulas you use on grills, those bad boys are scary. My dad had some really bad ass grilling utensils and to be honest I couldn’t tell if they were actually meant to be used to flip burgers or to assassinate political dissidents. I suppose you could write a good book called There is a Ninja in the Kitchen: Cooking with Saki and Swift Death (I’d buy it).
Growing up my brother and I were always responsible for doing dishes after dinner (my parents thought a dishwasher was an unneccesary materialist device — also our kitchen was really small). I’d wash the dishes and my brother would dry and put them away. Being brothers and acting the way that brothers often do we would regularly get into kitchen utensil fights. My brother would hit me in the back of the head with a whisk, I’d crack his knuckles with a wooden mixing spoon, he’d slap me in the face with a spatula, I’d go for the meat tenderizer, and just then my dad would walk in and start the yelling. Something like, “Stop fucking around and finish the dishes!” My dad has a wonderful sense of humor but he never could quite appreciate brotherly kitchen brawls (which is strange considering he grew up with two brothers who he supposedly fought all the time). I remember one time my brother hit me with a pizza paddle (big wooden board used to take pizzas off a pizza stone) and I retaliated with a cookie sheet. God we had good times.
General Lordisimo's Apocalypse 
You could crack skulls with wooden utensils.
I had a friend growing up, he was big dude, son of a pro football player and soon to be college football player himself who used run in fear from his mother when she threatened him with a wooden spoon. It was worse than a belt, a switch, or bullet.