(updated January 3, 2019)
crib rails (the gap between each bar), a cracker (the space around each grain), a sippy cup (the holes at the spout), an outlet faceplate (three prong holes), a cup (the hole you drink from), a door (the gap between the fitting and the frame/the key hole), a window screen (the space between each mesh square), carpet (the space around the fibers), clothing (the gaps between the warp and weft), a diaper (around each gusseted leg and the waist line), a towel (the space between fibers), a fork (space between the tines), a newspaper (around each wood fiber), a floor grate (the holes between each slat)
scissors (finger holes), drain (water holes), bobbin (gap around the barrel, center of the hub), needle (eye), door latch (inner hole of hub for door handle axis), wheel (center hole of the hub), button (eyes/corresponding button hole), dust pan (flat or curved scoop), pipe cleaner (gaps between bristles), sponge (pores), spirit level (bubble), trowel (flat or curved scoop), spade (slightly angled scoop), rotary blade (hub), bicycle chain (cutouts between links), cone wrench (u shaped cutout), crank spanner (hex bolt shaped cutout), tire lever (c shaped cutout), spoke wrench (spoke nipple indentation), bike pump (hand operated piston), pipette (inner cylinder), vise-grip (space between the jaws, hub, inner space around spring, space within grips), pliers (space between jays, hub, inner space within grips), baster (inner cylinder), bottle opener (space around the lever), bowl (inner), spoon (dish), sieve (small holes for particles), fork (gaps between tines), cake server (area above the flat face), garlic press (inner scoop and holes on the face), potato peeler (oval or rectangular shaped slot in the face), colander (inner bowl and holes), funnel (inner pipe and conical dish), corkscrew (space around the twisted screw), chinoise (conical inner area and small holes), cheesecloth (gaps in weave), cherry pitter (gap for lever and inner void the size of a spherical nickel), egg poacher (inner dish and holes), egg separator (slots between the spiral cone shaped head), egg slicer (slotted dish and area around individual wires/blades), fish scaler (slots and grooves), flour sifter (gaps in wire mesh and handle lever), slotted spoon (slots), grater (holes and divots), ladle (dish), lemon reamer (grooves), juicer (donuts shaped dish and grooves), mandolin (rectangular slots), pick ( gaps between tines), measuring cup (dish), measuring spoon (smaller dishes) , meat tenderizer (grooves), mortar (dish and miniscule granular divots in base), nutcracker (grooves in head and gap for nut), oven mitt (inner space generally shape of a hand), pastry bag (conical tip), pastry blender (area around each individual blade, ricer (inner scoop and holes on the face), poultry shears (area between blades), roller docker (space around prickly heads), rolling pin (inner hub), salt shaker (holes in face), spider (holes in mesh basket), whisk (area around wire loops), wooden spoon (shallow inner dish), zester (spaces around perforated head)