These are all the Simpsons Couch Runs remaining.

Do your part!

I've listed here every episode that these couch runs occur on. If you've got an old tape with these episodes or one of the compilation sets, it is your civic duty to assist in this endeavour!

1 Bart is squeezed off and pops into the air; during the shot of the TV, he is seen coming down 7G02 "Bart the Genius"
7G07 "The Telltale Head"
2 The couch falls apart when everybody is on it 7G03 "Homer's Odyssey"
7G10 "Homer's Night Out"
9 Maggie ends up in Marge's hair

7F05 "Dancin' Homer"
7F16 "Oh Brother, Where Art Thou?"

11 Grampa is lying on the couch sleeping 7F07 "Bart vs. Thanksgiving "
7F17 "War of the Simpsons"
14 Homer bumps the others off the couch 7F10 "Bart Gets Hit by a Car"
7F20 "War of the Simpsons"
27 Everybody except Maggie bang their heads together and lie unconscious on the floor 8F13 "Homer at the Bat"
29 The couch swallows everybody as it transforms into a monster

8F18 "A Streetcar Named Marge"
9F15 "Last Exit to Springfield"

30 The couch rotates 180 degrees through a secret door in the wall; an empty couch takes its place 9F01 "Homer the Heretic"
9F12 "Brother from the Same Planet"
31 As Maggie is already seated, Homer, Marge, and Bart run "past the edge of the film" and scurry back to the couch 9F02 "Lisa the Beauty Queen"
9F14 "Duffless"
32 Simpson-sized skeletons sit on the couch  
33 The couch deflates (as if filled with air) 9F03 "Itchy and Scratchy: The Movie"
37 Everybody is "miniature" and must climb the "giant" couch; Maggie has to be pulled up 9F09 "Homer's Triple Bypass"
9F20 "Marge in Chains"
38 Everybody sits, just before the room is filled with other regular characters 9F10 "Marge vs. the Monorail"
39 Everybody gets caught in a net that was spread on the floor

9F11 "Selma's Choice"
9F19 "Krusty Gets Kancelled"

40 Everybody runs into each other and shatters on the floor; Santa's Little Helper examines the damage 1F08 "$pringfield"
1F21 "Lady Bouvier's Lover"
42 Everybody runs into each other and there's an explosion; eventually, the pacifier lands and bounces away 1F09 "Homer the Vigilante"
1F20 "Secrets of a Successful Marriage"
43 Everybody, plus the couch, is crushed by a foot that is reminiscent of how Monty Python's Flying Circus opens [1F02] Homer Goes to College
[1F12] Lisa vs. Malibu Stacy
[2F33] Another Simpsons Clip Show
45 A Zombie Simpson family crashes through the floor from below and sits on the couch [1F04] Treehouse of Horror IV
46 The couch is painted on a wall, which everybody runs through [1F03] Marge on the Lam
47 A fat man takes up most of the couch; everybody squeezes into the tiny spot remaining [1F05] Bart's Inner Child
[1F13] Deep Space Homer
49 Everybody sits, then notice they're on the set of Late Show with David Letterman as "Dave" turns face forward [1F07] The Last Temptation of Homer
[1F19] The Boy Who Knew Too Much
50 Everybody pokes their head up from behind the couch (Maggie does it from behind a cushion on the couch) [1F10] Homer and Apu
51 Everybody sees two couches, then they each split into two halves, each half sitting on a couch [1F14] Homer Loves Flanders
52 Everybody is shaped like a ball and bounces around before landing on the couch and returning to normal [1F16] Burns' Heir
53 Everybody sits, then Homer gets up, rips the FOX logo from the screen corner, and they all stomp on it [1F18] Sweet Seymour Skinner's Baadasssss Song
56 Everybody is "beamed aboard" the couch in original "Star Trek" style (complete with sound effect) [2F01] Itchy and Scratchy Land
57 Everybody enters with a mismatched head and limbs (for example, one of Bart's legs is now Lisa's right arm, and Lisa's arms are where her legs should be) [2F03] Treehouse of Horror V
60 Everybody runs by the same TV and couch again and again, all except Maggie grinning the whole time [2F07] Grampa vs. Sexual Inadequacy
[2F16] Who Shot Mr. Burns? Part One
65 As the couch moves aside, everybody lines up in front of a police lineup height chart [2F20] Who Shot Mr. Burns? Part Two
87 Everybody flies in on jet-packs; Maggie flies in last and lands on Marge's lap [3G01] The Springfield Files
92 The couch is sliding on the deck of a ship; when everybody (in raingear) sits on it, they are covered by a wave 4F13 "My Sister, My Sitter"
103 The floor is a treadmill; Homer falls and says "Marge, stop this crazy thing!" George Jetson-style 5F24 "All Singing, All Dancing"
144 Everybody lands on the couch via a Futurama-style tube, except that Fry is in place of (and is then sucked up and replaced by) Bart BABF22 "HOMR"