I would say "Mirror, Mirror" has to be listed in the canon. The influence of Evil Spock With A Beard on the popular gestalt is not to be underestimated. I will go out on a limb and say that "Spock's Brain" from the last season, I believe, (in which an alien race steals Spock's brain to replace the master computer controlling their culture; and in which Spock must direct McCoy in the delicate surgery to replace his brain in his own skull - as he is being operated on!) also should be ranked in the canon. Many would raise their voices in opposition to this proposition, pointing out that something so egregiously horrible could not be genuine Star Trek. Those people, however, fail to realize that the episode was a brilliant self parody. This is manifestly evident because such a ridiculous story could not have been put forth seriously -- could it?

Brad - Stephenson answered this question back in 1992. "When it gets down to it - talking trade balances here - once we've brain-drained all our technology into other countries, once things have evened out, they're making cars in Bolivia and microwave ovens in Tadzhikistan and selling them here - once our edge in natural resources has been made irreelvant by giant Hong Kong ships and dirigibles that can ship North Dakota all the way to New Zealand for a nickel - once the Invisible Hand has taken all htose historical inequities and smeared them out into a broad global layer of what a Pakistani brickmaker would consider to be propserity -y'know what? There's only four things we do better than anyone else music movies microcode (software) high-speed pizza delivery" -- Neal Stephenson, SNOW CRASH. Okay, so maybe he was wrong about microcode. We've still got music, movies and pizza delivery.