Chopsticks

Chopsticks come in various forms from cheap, disposable, wooden pairs to finely crafted metal utensils.

Uses

Stabby ends, duh. Works great on ribs, finger webbing, fleshy bits, under the jaw, behind the ears, bottom of feet
Similarly, they make a nice impromptu kubotan for pressure points
Sushi pinch sensitive bits (nipples, septum, ears, clit)
Dragging/rolling over bones (side ribs particularly effective)
Kneeling on them
Held between back of thigh and calf vertically while kneeling/squatting
Held with finger tip against wall with arm outright at 90 degrees for long periods; flat or by the ends depending on how evil you feel, sharpened finger end if a brat is particularly deserving
At arm's length, they sting like a motherfucker when used as a switch
They can be fractured to produce splinters that are historically torturous

Splinters present an infection risk. Please use appropriate safety precautions.