Joel Robinson Era

Episode Joel's Invention The Mads' Invention
101- The Crawling Eye Electric bagpipes
Canine antiperspirant
102-The Robot vs the Aztec Mummy Airbag helmet
102 - The Robot Vs The Aztec Mummy (Shout Vol. 15).mkv snapshot 00.02.14 -2017.03.15 16.52.48-
"Chalk Man" record and security system
103- Mad Monster Hell-in-a-handbag
Acetylene-powered thunder lizard
104- Women of the Prehistoric Planet Toilet paper in a bottle Clay and Lars' Flesh Barn
Clay and Lar's Flesh Barn-0
105- The Corpse Vanishes Chiro-gyro
Flame throwing flower
106- The Crawling Hand Safety saw Limb lengthener
107- Robot Monster Cumber-bubble-bund Methane whoopee cushion
108- The Slime People Cartoon eyeglasses Screaming cotton candy
109- Project Moonbase Juggling water Insect-a-sketch
110- Robot Holocaust Nitro burning funny pipe Stocking mask of the future
111- Moon Zero Two Teleporting food Celebrity mouth to mouth toothpaste
112- Untamed Youth Never-light pipe Tongue puppets
133- The Black Scorpion Giant party favor Mads have mutated
01.MADS-The Black Scorpion-Screen shot 2011-02-14 at 12.59.00 PM
201- Rocketship X-M BGC-19 drum machine
BGC-19 drum machine
202- The Side Hackers Joel's pet slinky Dr. F.'s slinky body
203- Jungle Goddess Radio controlled circular saw Dr. F.'s head is fused to a sax
204- Catalina Caper Tickle bazooka
Tank tops
205- Rocket Attack USA Candy adding machine
Water-polo foosball
206- The Ring of Terror Pin-bolus
Life-size "Operation" game
207- Wild Rebels 3D pizza Hobby hogs
208- Lost Continent No invention Exercise variations
209- The Hellcats Sign language translator
No invention (but they do yell NOOOOO!)
210- King Dinosaur Incredibly stinky sweat socks The pocket scientist
Pocketscience 2
211- First Spaceship on Venus Junk drawer helper Invention lost in MADs junk drawer
212- Godzilla vs. Megalon Easy-to-make Halloween costumes
MST3k 212 GvMegalon Invention Exchange- Joel and Bots
More Halloween costumes
MST3k 212 GvMegalon Invention Exchange- The Mads
213- Godzilla vs. the Sea Monster Mind controlled guitar
MST3k- The SOL crew's invention exchange for Godzilla Vs. the Sea Monster
Doggie chew toy guitars
MST3k- The Mad's invention exchange for Godzilla Vs. the Sea Monster
301- Cave Dwellers Smoking jacket Robotic arm wrestling
Wpid-screenshot 2015-09-02-23-04-15
302- Gamera Endless salad bar
Gamera MST3K Endless Salad Bowl thumb-1
Bird cage vacuum
Gamera MST3K Invention Exchange thumb
303- Pod People Monster chord
Pod People Monster Chord
Public domain "karaoke" machine
MST3k- The Mad's Public Domain Karaoke Machine in POD PEOPLE host segment
304- Gamera vs. Barugon Soda can animation Disco cumber-bubble-bund
305- Stranded in Space "Bang"-gun variations
"Bang"-gun variations
306- Time of the Apes Cellulite phone
MST3k- SOL crew's invention exchange in Time of the Apes
Miracle growth baby formula
MST3k- The Mads' invention exchange in Time of the Apes
307- Daddy-O Air freshener mobile
Alien teething nook
308- Gamera vs. Gaos Fax tissue dispenser Self image printers
Self Image Printers
309- The Amazing Colossal Man Non-permanent tatoos A plant that reviews music
A Plant that Reviews Music
310- Fugitive Alien Musical chair
MST3k- Joel's Xylophone chair invention exchange in Fugitive Alien
Eye, ear, nose, and throat dropper
MST3k- Fugitive Alien- The Mad's Invention Exchange
311- It Conquered the World The "Sony Seaman" Hanged man costumes
312- Gamera vs. Guiron Collapsible trashcan
Gamera vs. Guiron- Collapsible trash and
Racy rorschachs
313- Earth vs. the Spider CD blow drier Cheese phone
314- Mighty Jack Ear-shaped earmuffs
Ear-Shaped Earmuffs-0
Formal flippers
Formal Flippers-0
315- Teenage Cave Man Rainy day epicacs
Nothing (Mads fight)
316- Gamera vs Zigra Crow-ka-bob Three Stooges guns
317- The Saga of the Viking Women and Their Voyage to the Waters of the Great Sea Serpent Literal "Waffle iron" Meat re-animator (for vegetarians)
318- Star Force: Fugitive Alien II The big head
MST3k- Joel's Big Head invention exchange in Star Force- Fugitive Alien II
Big noses
MST3k- The Mad's nose invention exchange in Star Force- Fugitive Alien II
319- War of the Colossal Beast Between-meal mortar Breakfast bazooka
320- The Unearthly Celebrity products Hard to swallow pills
321- Santa Claus Conquers the Martians Misfit toys Wish squisher
322- Master Ninja I Pop-up books for adults Boil-in-a-bag IVs
323- The Castle of Fu Manchu Extremely useful phone circuit/the big head again Joe Besser "Stinky" bomb
324- Master Ninja II Perpetual hamster habitat Conveyor belt buffetb
Conveyer Belt Buffet
401- Space Travelers The dollaroid Facial tissue
402- The Giant Gila Monster Sitcom radio Renaissance festival punching bags
403- City Limits Mr. meat and potato head Pop star Tupperware
MST3k City Limits- MN as Morrissey
404- Teenagers from Outer Space Scratch and sniff report cards Resusci-Annie ventriloquist doll
405- Being from Another Planet Jack Palance impersonation kit Tragic moments figurines
Tragic Moments Figurines'
406- Attack of the Giant Leeches Insty-adolescence kit Patches the leech
407- The Killer Shrews Jim Henson's Edgar Winter Babies
Mst407 - Edgar Winter Babies
The Mads try to destroy the Earth
408- Hercules Unchained The Steve-O-Meter
Decorator Roaches
409- The Indestructible Man Cereal Novels
Secret Invention
410- Hercules Against the Moon Men Super freak-out kit Deep Hurting!
TV's Frank & Dr Forrester; DEEP HURTING!
411- The Magic Sword Big gulp berets
Designer bio-hazard absorbent throw pillows
412- Hercules and the Captive Women The womb mate The lawn baby
413- Manhunt in Space Recycled paper clothing Beanbag pants
Beanbag Pants
414- Tormented Aunt Catherine Wheel Drinking Jacket
415- The Beatniks Pocket pool
Good-Luck Troll costumes
416- Fire Maidens of Outer Space Nike Air Chalada
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Big checkbook
Big Checkbook
417- Crash of Moons Rock and wreck guitar Sugary Deep 13 toothpaste
418- Attack of the the Eye Creatures Funny gag fax Router Ouija board
419- The Rebel Set Abstract paint-by-number kit Quick primp kit
420- The Human Duplicators Beanie chopper
William Conrad fridge alert
421- Monster A-Go Go Non-violent action figures
Johnny Longstorso
421 042
422- The Day the Earth Froze Snacktion
Unhappy meals
423- Bride of the Monster Microwave Faith popcorn The tough love set
424- Manos: The Hands of Fate The cartuner
MST3k Manos- Joel and crew invention exchange is The Cartuner
Chocolate bunny guillotine
MST3k Manos- The Mads Chocolate bunny guillotine invention exchange
501- Warrior of the Lost World Bittersweet Hearts
The square master
502- Hercules Instant karma Cellular desk
503- Swamp Diamonds Andrew Lloyd Weber Grill
MST 27
504- Secret Agent Super Dragon Micro-golf
MST 26
Virtual comedy
505- The Magic Voyage of Sinbad Rat Pack chess set
506- Eegah Pork-orina
Replacing Frank's blood with anti-freeze
507- I Accuse My Parents Junk drawer organizer
Junk Drawer Organizer
Cake 'N' Shake
508- Operation Double 007 Sarah the bobbin buzzard Lederhosen-hosen
509- The Girl in Lovers Lane "Don Martins" Evil baseball promotions
510- The Painted Hills Back-talk Cholester-do all
511- Gunslinger New whiffle items The scanner planner
512- Mitchell Daktari stool
None (Mads are being audited)

Mike Nelson Era

Episode Mike's Invention The Mads' Invention
513- The Brain That Wouldn't Die The gutter bumber shoot
The dream buster
514-Teen-Age Strangler The waiter-baiter
515- The Wild Wild World of Batwoman Razor-back Atomic powered hair dryer
516- Alien from L.A. Fridge udders
517- Beginning of the End New playing cards Re-comfy bike
518- The Atomic Brain The Mads
Crow and Tom Servo
519- Outlaw Fabio Kit
Really real time machine
612- The Starfighters Cowboy Mike's Red Hot Ricochet Barbecue Sauce
Cranial Ports

Jonah Heston Era

Episode Jonah's Invention The Mads' Invention
1101 - Reptilicus Bubble Fan
1102- Cry Wilderness Turkey-Theremin Carvel Clock
1103- The Time Travelers Dr. Crow's Old Time Edible Silica Packets Afterlife Alert
1104- Avalanche Mouth Vacuum Don la Font-aine 3000
1105- The Beast of Hollow Mountain Disco Cannon Titanic Hot Water Cannon
1106- Starcrash BB-Servo Band-eat-o
1107- The Land that Time Forgot M. Night Shyamalan Living Elder Pump
1108- The Loves of Hercules Fried Turkey Dunk Tank Mexican Jumping Beanbag Chair
1109- Yongary - Monster from the Deep Tiny Desk Hitler Coffee
1110- Wizards of the Lost Kingdom Verbal Smoke Bombs Sponsor Clock
1111- Wizards of the Lost Kingdom II GIF Notes Punt Bunnies
1112- Carnival Magic Yeasta Pet Flavor Sweat
1113- Il Natale Che Quasi Non Fu (The Christmas that Almost Wasn't) Re-Gifter Humbug FM
1114- At the Earth's Core Permanent Temporary Tattoos Rip Taylor Urn Cannon


  • After Joel Hodgson left the series, Best Brains tried continuing the invention exchange for a few episodes. They were soon phased out to accommodate Michael J. Nelson's less prop-oriented brand of humor.
  • The invention exchange was eventually brought back for Season 11.