Done to ridiculous extremes on The A-Team. Lettuce cannons, taffy bazookas....
Lampshaded in the Cop Parody Police Squad! In one episode, mobsters would attack Leslie Nielsen with improvised weapons of various ridiculousness, escalating from a knife, to a golf club, to a signed Picasso, to Herpes.
"Look out, he's got a cold sore!"
Many Police Procedural episodes have a plot twist in which the murder weapon is something unexpected. An episode of Alfred Hitchcock Presents ("Lamb to the Slaughter", one of several episodes based on short stories by Roald Dahl) had the police actually eating the evidence, a previously frozen leg of lamb.
"What we're looking for is something about the size of a large club. chew chew" "I've got a feeling it's right under our noses."
Among television shows, MacGyver was noted for his ability to ad lib weaponry, although he favored more complicated solutions than most TV heroes.
The series The Equalizer had as its main character a middle-aged retired spy who helped New Yorkers in need as penance for being such a lethal character over the years. He preferred non-violent solutions to his problems, mixed with a little gunplay. However, to establish how dangerous a man he was, the stories occasionally showed him improvising weaponry. In one case, he was being held hostage and asked to be escorted to the men's room. Once inside a stall and out of sight, he unscrewed the coat hook from the door and clutched it firmly in his fist so the less-than-an-inch long screw projected past his knuckles. As he left the stall, he punched his terrorist guard directly in the forehead, killing him instantly.
In Chuck, Casey has knocked out thugs using a refrigerator door, a microwave, a piece of a headboard he'd been cuffed to, and a radiator he ripped out of a wall.
Sarah makes a subspecialty of this. She's attacked people using wooden skewers, a bar of soap in pantyhose, a plate used discus-style, a frying pan, knives she found in a pile of wedding presents, a pipe she ripped out of a shower, a bust of a cougar, a broken CD, and anything else she could get her hands on. Oh, and she once hit a steering wheel so hard the airbag went off and knocked her opponent unconscious.
Chuck once used his own casted foot and a cane to knock a guy out.
One of the all-time classic examples is the Star Trek episode "Arena", where Kirk, who's stuck on a planet with an angry Gorn there, finds the ingredients for gunpowder and builds a makeshift cannon.
Galaxy Quest naturally skewered this one: Jason Nesmith (who played the Kirk-analogue Captain Taggart) is unarmed and running from a huge rock monster. When he asks the crew on the ship for advice, one of them tells him to see if he can "form some sort of rudimentary lathe" (and is promptly shouted down by his less Genre Savvy companions). Both are based on the short story "Arena" by Fredric Brown, published in 1944. The Star Trek version is closer to the original than the Galaxy Quest one, so much so that the credits for the Star Trek episode carry a story credit to Mr. Brown, in order to avoid copyright issues.
In the episode "Gray 17 is Missing", Garibaldi (who has a few bullets, but no gun) defeats a monstrous Zarg by stuffing the bullets into a steam pipe and using the head and pressure to fire them one at a time. Don't try this at home — if they fire at all, it'll be all at once, and slowly. And you'd also be likely to blow your own hand off in the process.
In a more dramatic event, during a battle in the Earth-Minbari war a Minbari shuttle lures an EarthForce strike group to a precise location...and at least one vessel is destroyed when Minbari warships open jump points that intersect their hulls. (The Minbari were obviously just showing off at that point. Unless they Warrior Caste is much less like humans than they seem, there was probably a bet involved.)
Utilizing the ability of the White Star class ships to open their own hyperspace portal and their speed, Sheridan opens a portal inside of an activated jump gate, destroying both the Shadow vessel that was chasing it and the gate that was being used by scavengers to loot a dead race's world, the latter an intentional secondary effect.
This was actually a tactic EarthForce had devised during the Earth-Minbari War. Only, Earth had no ship with both the ability to open a jump point and the speed to escape the explosion, so it was only a way to try and take down some Minbari ship down with them.
In Lost, Sayid kills someone with a dishwasher... more precisely, a row of knives faced up in the dishwasher tray.
On Lost Hurley once memorably threw a hot pocket at Ben.
In one episode of Stargate Atlantis, Ronon Dex is trapped on his homeworld, being hunted by Wraith. Although he soon finds a large assortment of weapons, he begins by fashioning a crude knife by tying a shard of metal to the broken off handle of a saucepan.
In another episode, he's cornered by a Wraith in the SGC base without a weapon. So he rips a pipe right out of the ceiling.
In an episode of Sanctuary, Helen Magnus is trapped in a warehouse by a masked assailant. She defends herself by screwing a bunch of pipes together to make a billy club.
Among other things, Michael Westen on Burn Notice has improvised stainless steel knuckles from a butter knife, a silencer from a tin can, a trigger spring from a bobby pin, and explosives from a wide range of unknown materials.
He claims you can make many of these explosives from things available under most kitchen sinks.
In one episode of The Sentinel, Blair Sandburg takes out one bad guy with a vending machine and another with a restroom door. Another time he throws a baseball, still another a fire hose, and one time uses a magnetic crane to pick up the bad guys' car—with them in it.
On Buffy the Vampire Slayer, vampires can be killed by driving any sharp piece of wood into their heart, and Buffy frequently exploits this. She has used (among other things) sticks, a wooden 2x4, a mop handle, a drumstick, a pool cue, and a #2 pencil. Occasionally, she will instead decapitate a vampire with an improvised weapon, from a thrown cymbal in the pilot, to closing a car door on a vampire's neck in season 6.
Willow also used the #2 pencil. With a little telekinetic magic.
Buffy did it first, in Ep: 306 "Band Candy". Buffy and Giles are sitting in a graveyard, studying for Buffy's SATs, (homework... with vampire slaying!) when a vamp appears behind Giles.
Buffy: Roll. Giles: What? (turns, sees vamp, and rolls away) Buffy:(after dusting the vamp with her pencil) Hmm. I broke my No. 2 pencil. We'll have to do this again sometime.
(Giles calmly produces another pencil)
Buffy also hit Xander with a desk (offscreen) while he was under the influence of the hyena spirit in Season 1.
Spike lampshades this in "Halloween". He arranges for a mook to videotape Buffy in action, then reviews the tape so he can learn how to defeat Buffy. He is particularly impressed when she stakes the vampire with a signpost.
In "Spiral" Buffy is being chased while driving a motorhome. She shouts out for a weapon, causing Spike to reply, "Hello? You're driving one!"
In fact, improvised weapons are frequently the order of the day on the show. Apart from the various items used to stake or decapitate vampires, the various characters have used baseball bats, crowbars, kitchen knives, fire axes, ice skates, frying pans, tables, and a wrecking ball.
Buffy also mentions an incident prior to her arrival in Sunnydale, where all she had to work with was a nail file to cut a vampire's thick neck.
She once used a shard of broken church glass as an improvised chakram to cut the gauntlet-wielding hand off an ex-Watcher.
A particularly memorable case comes when she uses a ceramic unicorn with a wooden horn. Lampshaded when Buffy looks at it in confusion afterward and throws it down.
This is in Angel, when Angel kills a werewolf with a pen he borrows from Wesley. Later, when they're discussing the werewolf:
Spike: I had a wee spat with a werewolf myself once. Fought for over an hour. Brutal, vicious. (holds up his hand, wiggles his fingers) Almost lost my— Fred: Angel killed him with a pen. Spike:....
Also on Angel, Harmony fights another vampire in the Wolfram & Hart cafeteria. After a few rounds of vampire fisticuffs, they both grab chopsticks. The best human analogue would probably be steak knives.
Angel throws a spoon at one guy that lodges itself in his head and kills him.
Spike: A spoon? That's just - (butler pulls spoon out) Well. Okay, that's more - (butler falls over dead) disappointing, really.
Fred kicks a lot of ass when it comes to this. For example, she designed a giant mousetrap-like device that fires an axe when stepped on. Because she was Crazy Preparing for the possibility of fighting an enemy while armless.
Done several times in Highlander: The Series. There are only so many ways to cut off a head with a sword. If said head gets in the way of a wrecking ball, or stuck in a motorboat prop, well, whatever gets the job done.
Note that he earlier disarmed his knife-wielding opponent with an egg whisk.
He once engaged in battle with a few mooks, one of whom was in a car. While fighting with 2 mooks, a third guy is trying to get out of the car and join the fight. This resulted in Eliot repeatedly kicking the door into him telling him to "Stay in the car!".
He once took out a group of former British special forces using a belt as a weapon.
Also, Eliot's Foil Mikel Dayan would mop the floor with you. Because she once killed a guy with a mop.
An episode of Life features a female Professional Killer who is very skilled at this. Her entire shtick is using household objects to kill people. One really good scene features Charlie talking to her in her kitchen, and constantly looking around at everything in the room that he could be killed with at any time. He then one-ups her by asking for a soda as he leaves, and pouring it in her gas tank so she can't get away once she disables his less savvy partner.
During an episode of Power Rangers RPM a bunch of the Grinders attack a mom sitting with her baby, the baby in the carriage. 2 of the Rangers show up, and Scott at one point in time picks up the carriage and swings it around at the grunts, managing to knock them down. All this is done while said baby is still in the carriage. And yes, he looks inside at one point to make sure the baby is okay.
This happens pretty consistently in RPM. If they can get their hands on it, it's been used as a weapon. Bus doors, vegetables, a beach umbrella, suran wrap, Flynn's transformation explosion. If it can smash, cut, entangle, entrap, or otherwise inconvenience the Grinders or the Monster of the Week it has.
In an episode of Jonathan Creek, the title character stops an armed man with a thrown playing card. Lampshaded and slightly justified in that he got the book "Cards as Weapons" by Ricky Jay at the start of the episode, was seen practicing the moves during the show, and admitted after his success that he had actually missed the target he was aiming for.
Mal, Zoe, and Jayne make heavy use of improvised weapons. Mal has a tendency to turn opponents' weapons against them, at one point choking an Alliance soldier with his own rifle's strap and the chains on his handcuffs to break a Reaver's neck.
Wash, the ace pilot, manages to improvise the mule to knock out a Mook at one point
Shepard Book uses a hose and a water pump to incapacitate multiple thugs.
Waif-Fu River can use just about anything at hand. When she goes berserk in Serenity she uses a serving tray and a glass bottle (kicked across the room into the head of someone running across the room) as weapons. In "The R. Tam Sessions" tie-in, she also kills a man using a pen.
The short-lived TV series Spy Game has Lorne Cash doing this all the time, including a scene where he faced off against his teacher, and they were declaring what could be used in that fight. "Kick that garden hose away." "Get rid of the comb in your back pocket." "Take off your watch..."
In the episode "The Farm", Kara Thrace uses a shard of broken mirror to stab a Cylon in the neck.
Very iconic Battlestar Galactica example is Adama beating Leoben to death with a flashlight in the Miniseries.
Leoben also gets a pair of metal chopsticks in the neck from Kara after he locks her up in a mock apartment and deprives her of anything else he thinks can be used as a weapon (including steak knives).
In an episode of McCloud, Sam McCloud used a couple gallons of liquid detergent and a firehose to defeat a small army of armed killers breaking into poilce headquarters.
This trope pops up a lot in Misfits, sometimes played for comedy (Nathan attacking the security guard with a stapler for instance), and sometimes through sheer necessity — such as when Kelly incapacitates Tony with a paint tin, or when Simon uses a broom to break the lightbulbs in the community centre (though that one was more for creepiness value than anything).
In FlashForward (2009), Mark Benford is blackmailed into coming to a deserted area with no support or weapons by the genius Dyson Frost. When they meet face to face, Mark asks to take a drink of water, then spits into Dyson's face, revealing the bottle to have been filled with gas from his car.
In one episode of Legend of the Seeker imprisoned Kahlan makes herself a weapon by folding a plate and proceeds to kill a guard with it.
On the 1966 Batman, improvised weapons were a recurring part of the fight choreography, used by heroes and villains alike. Batgirl, however, was especially prone to using them, most likely because the producers wouldn't allow her to give or receive punches. Whacking a bad guy over the head with a handy prop helped add a little variety to Batgirl's ballet-influenced Dance Battler fighting style.
On The Vampire Diaries, the newest Dragon uses a handful of coins to shatter special UV-protective glass in front of a local vampire hangout, causing the patrons to immediately fall to the floor screaming.
Sammo Law of Martial Law employs this to great effect, much like his fellow Peking Opera House graduate Jackie Chan. The shows premise specifically says he can't have a gun, just so they'd have an excuse for this trope.
The pilot involves a jerk cop reading his jacket and finding that it declares he can turn anything into a "deadly weapon". He loudly and publicly challenged Sammo to fight him with a blackboard eraser. He lost.
The team later encounters an assassin who has a reputation much like Sammo's, including improvising a garrote from a paper napkin. Turns out it's all hot air.
This happens in Primeval. A lot. Cutter's make-shift flame thrower, Helen's exploding milk carton (or whatever that was), Claudia and her Golf Club of Death...I could go on and on.
Claudia: Hole in one!
To put it simply, the team often find themselves without effective guns or ammunition, and have to make do with whatever they can find.
Connor seems to do this more than anyone else. The Electric Footstool of Doom, the slushie cup, and the very scary Dart of Death, just to name a few. Oh, and that time when Stephen has a gun, Abby has a gun, and Connor gets...a shovel. Possibly justified by the fact that Connor never gets a gun. No wonder, after he shoots Abby and a man in a bear costume.
Cutter: Any questions?
Connor: Can I have a gun?
Cutter: Take a guess.
Cutter: Good guess.
When Connor and Abby get stuck in the past for a year, they have to make plenty of improvised tools and weapons in order to survive. This is also when Connor Takes A Level In Badass.
While not technically used as a weapon, Abby does at one point propose an unusual solution to clearing a poisonous, sulphurous fog when the ARC's armoury fails them - leaf blowers. The monster of the week, a species of parasitic Precambrian worm, is ultimately killed but a combination of air conditioning and an automated fire extinguisher system.
At least one predator (a dromaeosaurid, in this case) has literally been killed with an Anomaly.
Danny Quinn, upon returning briefly in the Season 4 finale, has a stout branch that he calls Molly.
In a flashback during the episode of NCIS where Director Vance recovers from a shooting, Eli David manages to take objects from around Leon's apartment in Amsterdam and forms them into a functioning Claymore antipersonnel mine as a defense against enemies pursuing them.
Mohinder from Heroes is fond of these, having used a ceramic elephant, a wall-sized map, a fire extinguisher, a car door, and a tuning fork (Makes Sense In Context). Sylar also likes his improvised weapons (broken glass, beer bottles, and assorted kitchen implements, among others), but almost anything's a projectile when you're telekinetic.
In the 2001 New Year's Eve of Eastenders, Little Mo smashes her abusive husband's face with an iron when he's assaulting her in a friend's kitchen (she was baby-sitting).
In the first episode of Young Blades, Jacqueline beats D'Artagnan by throwing a melon at him and squirting him in the face with milk from a strategically placed cow.
Alias - prime examples from the pilot being a car aerial and a chair (that Sydney was tied to at the time).
In Breakout Kings many of the escaping convicts use weapons made out of things they can obtain in prison; shivs are just the most basic of these. An explosives expert made a grenade from a lightbulb and flour. Another one build a trap in his cell that caused sharpened plastic spoons to pierce a guard's throat.
In Grimm, Juliette makes good use of a pot of boiling water against an ogre attacking Nick. In a later episode another Wesen also attacks her in the kitchen so he kicks him in the groin and then proceeds to whack him in the head with a frying pan.
In The City Hunter, Yun Sung uses, at various points, a spoon, a tie, a rolled-up calendar, and a walkie-talkie as weapons.
In the JAG episode "Code Blue" (second season), when a terrorist in a hospital demands that he identify himself, Harm claims his callsign is "Zapper". And then zaps the guy with a defibrillator.
Cold Case was loaded with these. Murder weapons included a skateboard, mantel clock, hand weight, tennis racket, car antenna, and of all things a metronome.
The title object in the Ellery Queen episode "The Adventure of the Chinese Dog". The choice of this weapon ends up being a plot point, as Ellery realizes that it would have been much easier to kill Eben Wright with the nearby fireplace poker.
"Irresistible": Agent Scully got kidnapped by a terrifying Serial Killer and a death fetishist. She managed to hide in a wardrobe and as he opened it, she sprayed him in the eyes with a spray can, and ran off while he was stumbling.
"2Shy": In a victim's apartment, Agent Scully goes to the bathroom to look for medical supplies. The Monster of the Week Incanto suddenly appears and smashes her head into the mirror. She uses her Combat Stilettos to kick him but he pushes her to the floor. She grabs and uses the nail scissors and stabs him in the chest. Then Ellen, the victim, shows up and just shoots him with Scully's gun which she left lying on the floor.
"Leonard Betts": Betts attacks Scully in an ambulance car. He comes at her with a scalpel and she fights him off. When he tries to attack her again, she turns the power on the defibrillators and zaps him on the head.
"Chimera": Jenny was fighting with a Monster of The Week in a motel room. The mirror above the bed shattered. She grabbed one piece of the broken mirror and slashed the shady figure's shoulder. Unfortunately, Jenny was killed after all.
Wheeler decapitates another with the door of the bus' suitcase compartment.
In Supernatural the Winchesters are often forced to fight with what is at hand. The ubiquitous nature of salt comes in handy with Dean using a small salt shaker delivered with his meal in prison to scare off a ghost and the rock salt used for salting roads to demon proof a police station.
In "'Til Death Do Us Part", the murder weapon turns out to be a processional cross that was in the room where the victim and his killer were arguing.
In "The Murdoch Identity", when Anna Fulford and Murdoch are confronted by his two armed pursuers in her pub, she tells Murdoch to duck before using a frying pan to hit one of the gunmen in the head.
In "Downstairs, Upstairs", the household objects used to kill include a fireplace poker and a chair cushion.
A geologist's pick has twice been used to kill, in "Dinosaur Fever" and "Murdoch of the Klondike".
In "Murdoch Ahoy", a man proved to have been stabbed to death with a specialized screwdriver.
In "Murdoch of the Living Dead", Dr. Grace uses her hatpin to stab a "zombie" that grabbed her arm.
In the B-plot of "The Death of Dr. Ogden", the victim is found with the murder weapon, a red snooker ball, jammed in his mouth.
Played for Laughs by Constable Crabtree in "Crabtreemania" when he finds himself suddenly in a professional wrestling match. After he fails to get the better of his opponent (including using a martial arts move he learned the previous season), his sweetheart Edna gives him a folded chair, which he uses to hit his opponent on the head and knock him out. George then hoists Edna onto his shoulder in victory to receive the cheers of the crowd.
Improvised weapons are everywhere in The Walking Dead, due to the awkward fact that zombies flock to loud noises like gunshots, and ammo is often hard to find in the post-apocalyptic setting. Characters have killed zombies with shovels, hatchets, crowbars, hammers, cars, heavy boots, furniture, and nearly anything else that will penetrate a skull.
The first half of the second season revolves around an object referred to as "the Obelisk" (more properly named "the Diviner"), which lethally petrifies anyone who touches it. HYDRA wants it so they can learn how to use its abilities as a weapon, and S.H.I.E.L.D. just wants to keep it from HYDRA. A man who knows more about its origins scoffs at this, saying it's not a weapon, it's a key with a self-defense mechanism.
HYDRA captures Skye and forces her to touch the Diviner. The second she finds out that she can do so without being petrified, she starts whacking HYDRA mooks with it. Unfortunately, they saw this coming, but she still manages to take out a few before the rest make her stop.
The New Avengers: In "Dirtier by the Dozen" Ganbit uses Purdey's bra as an improvised sling to knock out a commando.