If you've got some time, be sure to check out this great and detailed oral history of The Simpsons from Vanity Fair. It features anecdotes from, among many others, Conan O'Brien (who also has a typically entertaining interview), Pixar's Brad Bird, and evil billionaire/Mr. Burns-lookalike Rupert Murdoch (notably absent are Matt Groening, James L. Brooks, and Sam Simon, the show's three executive producers). Read the whole thing for such tidbits as the secret subplot of Rocky III that only Mr. T knows about and the time Hank Azaria discovered that Mick Jagger is kind of a dick.
Oh, and pay no attention to the accompanying list of the Ten Best Episodes. Any such list that contains no mention of "Last Exit to Springfield" is nothing but lies and deceit. To wit:
I rest my case.