Tosy and Cosh just did this. It's not a blog-meme thing, but it's just too good an idea to let pass. Soooo, here we go! (Quotes are approximate.)
1. "You must avenge my death, Kimba -- I mean, Simba."
2. "Check it out, Lis! If you play it one frame at a time, you can freeze the exact moment his heart breaks in pieces."
3. Maggie's enemy, the baby with one eyebrow.
4. Gerald R. Ford moving in across the street: "Homer, would you like to come over for beer and nachos?"
5. Homer's inability to stop thinking of Flanders in his ski suit: "It's almost like I'm wearing nothing at all!"
6. "An all-syrup Super Squishy? Such a thing has not been done!"
7. "Remove the Stone of Shame. Attach the Stone of Triumph!"
8. Leonard Nimoy's introduction of the X-Files crossover episode: "All the things you are about to see are true. And by 'true', I mean, 'false'."
10. "Me, fail English? That's unpossible!"
11. "Come on, people! This poetry isn't gonna appreciate itself!"
12. "Oh look, there's Mount Carlmore." "What does Carl think of that?" "Strangely, we've never discussed it."
13. "For fifty bucks, this better be the best beer ever! [sips] You got lucky there, Moe!"
14. The Flaming Moe.
15. She-Hulk versus Leon Spinks: "Worst crossover ever."
16. "Pray for Mojo...."
17. Homer walking through the paper walls in Japan.
18. "Hi, ev'reebody!" "Hi, Dr. Nick!"
19. Bart, human interest reporter: "Joe Banks... 82 years young has come to this pond every day for the past 17 years, to feed the ducks. But last month, Joe made a discovery... the ducks... were gone! Some say the ducks went to Canada, others say Toronto. And some people think, that joe used to sit down there, near those ducks. But it could be, that there is just no room in this modern world, for an old man... and... his ducks..."
20. "Yar, she blows!"
21. Springy, the Springfield Spring.
22. "Smithers, there's a rocket in my pocket!"
23. Mr. Burns, after listening to The Ramones: "Have the Rolling Stones killed."
24. "Will you take us to Mount Splashmore? Will you take us to Mount Splashmore? Will you take us to Mount Splashmore? Will you take us to Mount Splashmore? Will you take us to Mount Splashmore? Will you take us to Mount Splashmore? Will you take us to Mount Splashmore? Will you take us to Mount Splashmore? Will you take us to Mount Splashmore?"
25. "Press any key? Where's the 'any' key?"
26. Nelson's rationale for letting Bart handle his BB gun: "Sure, it never hurts to have another set of prints on a gun."
27. Nelson turning out to be a devoted fan of Andy Williams.
28. Mel Gibson's ultra-violent remake of Mr. Smith Goes to Washington.
29. Cletus, the slack-jawed yokel.
31. "And I, for one, welcome our new insect overlords!"
33. "Ahoy hoy!"
34. Bart gets a nice photo of himself made for his mom for Christmas.
35. Jasper as a substitute teacher during the teachers' strike: "That's a paddlin'."
36. Any time Homer screams.
38. The church congregation holding up candles and lighters in honor of the organist's rendition of "In-a-gadda-da-vida".
39. Great opening sequence: the "Powers of Ten" zoom, from the Simpson's living room out into space and then back into the world of the microscopic and back in the Simpsons' living room. Homer: "Wow."
40. The verb "embiggen".
41. Principle Skinner trying to convince Superintendent Chalmers that he refers to hamburgers as "Steamed Hams".
42. "We're gonna paint that wagon, we're gonna paint it good!"
43. "Who controls the British crown? Who keeps the metric system down? We do! We do!"
44. Bart distracting Sideshow Bob by betting him he can't sing the entire score to The HMS Pinafore.
45. Sideshow Bob and rakes.
46. The Simpsons enter the Witness Protection Program: The Thompsons!
47. Yvan eht nioj!
48. Homer's run as Springfield Garbage Commissioner: "I can't believe we're moving the whole town!"
49. Barney gives up booze...so Moe gets him addicted to cappuccino.
50. The 'J' in Homer J. Simpson stands for...Jay!
51. "Homer, this is the worst thing you've ever done!" "Marge, you've said that so much it's lost all meaning."
52. "Dad, do you even have a job anymore?" "I think it's pretty obvious that I don't!"
53. Flanders, after Homer's raided his garden: "But did you have to salt the earth so that nothing will ever grow there again?" "Heh heh...yeah."
54. Homer as football coach: "This is the easiest part of the coach's job: the cuts!"
55. "Luke be a Jedi, tonight!"
56. Ralph Wiggum: "That's where the leprechauns tell me to burn things!"
57. Y2K: Dick Clark's robot self melts and explodes.
58. Bart trying to impress his older female babysitter by wearing a smoking jacket and "smoking" his bubble-pipe.
59. The Springfield Isotopes.
60. Homer's inventions: electric hammer, recliner/toilet, chair that won't tip over.
61. Homer's sub crew singing "In the Navy".
62. "We're in international waters now, Bart! Look over there! That boat is rebroadcasting Major League Baseball with implied oral consent, not expressed written consent!"
63. Smithers feeding Mr. Burns spanish peanuts: "Skin!"
64. Frank Grimes.
65. Homer walking backwards all the way home after he sees Apu having an affair.
66. Jasper freezing himself at the Kwik-E-Mart.
67. Krusty's Comeback Special: "Send in...the clowns...."
68. Bart drinking twelve glasses of water to ensure he gets up early Christmas morning, and his ensuing surreal dream about having to go to the bathroom, with cheerleaders screaming, "Give me a P! We're number One! Go go go!"
69. Nelson as Lisa's first boyfriend.
70. "Marge, I'm not gonna lie to you. Well, goodbye!"
71. The Simpsons run out on Jeopardy! after running up a huge tab. One of Trebek's goons: "She ain't gettin' the home version."
72. The Springfield Symphony Orchestra, playing the shower scene from Psycho on the bus home.
73. The missile destroying the only bridge out of town when a meteor is going to hit Springfield.
74. Homer's bowling-ball beer bootlegging scheme.
75. Stealing the Springfield lemon tree.
76. Personages from PBS, including the Teletubbies, chasing Homer after he welches on his pledge-drive pledge.
77. "Listen to those bassoons! John Williams is rolling over in his grave!"
78. The Canyonero.
79. "Bart, do you think you can stop the casual swearing?" "Hell, no!"
80. The little city Lisa grows in a petri dish, which later dispatches a tiny spaceship to destroy Bart.
81. "Well, crying isn’t gonna bring him back, unless your tears smell like dog food. So you can either sit there crying and eating can after can of dog food until your tears smell enough like dog food to make your dog come back - or you can go out there and find your dog!"
82. "The Simpsons are going to ______!"
83. Homer on medicinal marijuana; he cuts himself shaving and bleeds little rainbows.
84. Abe Simpson dosing little Homer with Ny-Quil.
85. Maggie's first word, unheard by anyone else.
86. That Texan guy who fires off his two six-shooters pretty much at the end of every sentence.
87. Fox Mulder's ID badge, juxtaposed with a photo of himself in a Speedo.
88. Dana Scully, watching Homer on a treadmill: "His fat...it's like watching a lava lamp."
89. Homer's failure to get Mr. Burns to remember who he is.
90. Homer's ill-advised attempt to demonstrate to Lisa that Simpsons are not doomed to failure: "Should've researched this plan a little, eh, Dad?"
91. Bart gets a credit card.
92. Homer, after seeing Maggie all made-up by Lisa and her slumber-party friends: "OK, I'm goin' to Moe's."
93. Homer's time-traveling toaster, in which he flees a timeline where it rains donuts.
94. Bart as The Fly.
95. Lisa on jazz: "You have to listen to the notes that he isn't playing!"
96. Marge's crush on the Brawny paper-towel guy.
97. Maude Flanders's dream, the amusement park Praiseland, with the ride where a giant animatronic King David reads all of the Psalms to the captive riders.
98. Bleeding Gums Murphy.
99. Abe Simpson always falling asleep in mid-sentence.
100. Slurm. (Oh, that's Futurama. My bad.)