This reddit thread has some great ones but I’d love to hear some that Dopers have come up with.
Speak softly and carry a big stick. John Holmes.
“The Beatles are more popular than Jesus.” - Mick Jagger
[T]oday I consider myself the luckiest man on the face of the earth.
OJ Simpson October 3, 1995
“Show me your genitals, your genitals. Show me your genitals. GENITALIA!” - Bill Clinton
If the Hulk says “Hulk smash!” it’s an assertion; if Captain America says it, it’s an order.
On a similar note, given Doctor Doom’s tendency to speak in the third person, lots of his boasts sound entirely different if you imagine someone else saying them. “None can defeat DOOM!” - Reed Richards.
“The Beatles are more popular than Jesus.” - the Pope.
“L’etat ce moi” – Adolph Hitler
“Ask not what your country can do for you - ask what you can do for your country”
Oh my God, that thread is hilarious.
“The only thing we have to fear is fear itself” - any future victim in a Nightmare on Elm Street movie
“Friends, Romans, countrymen, lend me your ears”
Let them eat cake.
I can’t think of any right now, but I did like:
“Imagination is more important than knowledge.” Glenn Beck.