DRILL PRESS: A tall upright machine useful for suddenly snatching flat metal bar stock out of your hands so that it smacks you in the chest and flings your beer across the room, splattering it against that freshly painted part you were drying.
WIRE WHEEL: Cleans paint off bolts and then throws them somewhere under the workbench with the speed of light. Also removes fingerprint whorls and hard-earned guitar calluses in about the time it takes you to say, "Ouch...."
ELECTRIC HAND DRILL: Normally used for spinning pop rivets in their holes until you die of old age.
PLIERS: Used to round off bolt heads.
HACKSAW: One of a family of cutting tools built on the Ouija board principle. It transforms human energy into a crooked, unpredictable motion, and the more you attempt to influence its course, the more dismal your future becomes.
VISE-GRIPS: Used to round off bolt heads. If nothing else is available, they can also be used to transfer intense welding heat to the palm of your hand.
OXYACETYLENE TORCH: Used almost entirely for lighting various flammable objects in your shop on fire. Also handy for igniting the grease inside the wheel hub you want the bearing race out of.
WHITWORTH SOCKETS: Once used for working on older British cars and motorcycles, they are now used mainly for impersonating that 9/16 or 1/2 socket you've been searching for the last 15 minutes.
HYDRAULIC FLOOR JACK: Used for lowering an automobile to the ground after you have installed your new disk brake pads, trapping the jack handle firmly under the bumper.
EIGHT-FOOT LONG DOUGLAS FIR 2X4: Used for levering an automobile upward off a hydraulic jack handle.
TWEEZERS: A tool for removing wood splinters.
PHONE: Tool for calling your neighbour to see if he has another hydraulic floor jack.
SNAP-ON GASKET SCRAPER: Theoretically useful as a sandwich tool for spreading mayonnaise; used mainly for getting dog **** off your boot.
E-Z OUT BOLT AND STUD EXTRACTOR: A tool ten times harder than any known drill bit that snaps off in bolt holes you couldn't use anyway.
TWO-TON ENGINE HOIST: A tool for testing the tensile strength on everything you forgot to disconnect.
CRAFTSMAN 1/2 x 16-INCH SCREWDRIVER: A large crowbar that inexplicably has an accurately machined screwdriver tip on the end opposite the handle.
TROUBLE LIGHT: The home mechanic's own tanning booth. Sometimes called a drop light, it is a good source of vitamin D, "the sunshine vitamin," which is not otherwise found under cars at night. Health benefits aside, it's main purpose is to consume 40-watt light bulbs at about the same rate that 105-mm howitzer shells might be used during, say, the first few hours of the Battle of the Bulge. More often dark than light, its name is somewhat misleading.
PHILLIPS SCREWDRIVER: Normally used to stab the lids of old-style paper- and-tin oil cans and splash oil on your shirt; but can also be used, as the name implies, to strip out Phillips screw heads.
AIR COMPRESSOR: A machine that takes energy produced in a coal-burning power plant 200 miles away and transforms it into compressed air that travels by hose to a Chicago Pneumatic impact wrench that grips rusty bolts last overtightened 58 years ago by someone, and neatly rounds off their heads.
PRY BAR: A tool used to crumple the metal surrounding that clip or bracket you needed to remove in order to replace a 50 cent part.
HOSE CUTTER: A tool used to cut hoses too short.
HAMMER: Originally employed as a weapon of war, the hammer nowadays is used as a kind of divining rod to locate the most expensive parts not far from the object we are trying to hit.
MECHANIC'S KNIFE: Used to open and slice through the contents of cardboard cartons delivered to your front door; works particularly well on contents such as seats, vinyl records, liquids in plastic bottles, collector magazines, refund checks, and rubber or plastic parts.
DAMMIT TOOL: Any handy tool that you grab and throw across the garage while yelling "DAMMIT" at the top of your lungs. It is also the next tool that you will need.
GREASE GUN: A device used unsuccessfully to force grease into rusty, plugged up grease fittings. When not in use this device meters a steady drip of oil onto the surface beneath it and mysteriously weeps a coat of grease onto its outer surface, no matter how thoroughly it was cleaned before it was put away.
SNAP RING PLIERS: A tool typically used to remove or install circular clips from shafts and bores and launch them across the shop or into a gravel driveway
CHANNEL LOCK PLIERS: A tool whose primary purpose is to create large painful blood blisters on the palms of your hands while simultaneously rounding the heads off of bolts. Secondary use: See DAMMIT TOOL
I think I could add a few more:
WELDING HELMET: a cleverly designed device which allows molten metal beads to accumulate on ones face and glasses.
CRESCENT WRENCH: a dual purpose device used to rounding off bolts AND mashing knuckles simultaneously.
MICROMETER: see C-clamp
LARGE SOCKET WRENCH: see hammer
OHMMETER: holder for dead batteries