More specifically, Walter Cronkite's report: "From Dallas, Texas, the flash apparently official: President Kennedy died at 1 p.m. Central Standard Time, 2:00 Eastern Standard Time, some 38 minutes ago."
For Augustus of Ancient Rome, whoever delivered the news that Varus and his three legions had been annihilated in the Teutoburg Forest.
While on the subject of Ancient Rome, I believe "the die is cast" is probably the premier example of an ancient historical wham line. Julius Caesar uttered it as he violated Roman law, bringing his legion across the Rubicon and into Rome... and thus died the Roman Republic.
When France was being invaded by Nazi Germany, Winston Churchill went to Paris and on a meeting with the commanders, asked the leading general, Gamelin "Where is the strategic reserve?". Gamelin answered "There is none". Churchill later described hearing this as the single most shocking moment in his life.
"I have to tell you now that no such action has been taken and, consequently, this country is now at war with Germany."
"Today on June 22th 1941, without declaring war, Hitlerite Germany invaded the Soviet Union."
Monday Night Football, December 8th, 1980. Howard Cosell drops a bombshell on the audience in the midst of an otherwise uneventful game between the New England Patriots and the Miami Dolphins:
"We have to say it. Remember, this is just a football game, no matter who wins or loses. An unspeakable tragedy, confirmed to us by ABC News in New York City. John Lennon, outside of his apartment building on the west side of New York City, the most famous perhaps of all of The Beatles. Shot twice in the back, rushed to Roosevelt Hospital. Dead. On. Arrival."
"As of the 21st of this month, I signed Proclamation Number 1081 placing the entire Philippines under Martial Law" from Ferdinand Marcos.
"Seit 5.45 wird zurückgeschossen!" ("Since 5.45, we have been shooting back!") Spoken by Adolf Hitler just as the invasion of Poland began.
From a chat log between Private Manning and the man who blew the whistle:
Bradass87:"Hypothetical question: if you had free reign over classified networks for long periods of time... say, 8-9 months... and you saw incredible things, awful things... things that belonged in the public domain, and not on some server stored in a dark room in Washington DC... what would you do?"
Supposedly when Hitler announced his plan to conquer the rest of Europe, multiple people in the room had heart attacks. We don't know what exactly was said, but we know it was a whammy.
"My fellow citizens, in the difficult circumstances our country is experiencing, President Muhammad Hosni Mubarak has decided to give up the office of the president of the republic and instructed the Supreme Council of the Armed Forces to manage the affairs of the country." - Egyptian Vice President Omar Suleiman announcing President Hosni Mubarak's resignation in response to massive pro-democracy protests.
You can hear the shocked reaction in this video (at 2:20) to Dianne Feinstein's announcement: "As President of the Board of Supervisors, it's my duty to make this announcement. Both Mayor Moscone and Supervisor Harvey Milk have been shot and killed. The suspect is Supervisor Dan White."
A positive one: after asked when unrestricted travel between the DDR and the BRD would be allowed again: "Err, from this moment on, I think..."
The Declaration of Independence: "We, therefore, the Representatives of the United States of America, in General Congress, Assembled, appealing to the Supreme Judge of the World for the Rectitude of our Intentions, do, in the Name, and by the Authority of the good People of these Colonies, solemnly Publish and Declare, That these United Colonies are, and of Right ought to be, Free and Independent States; that they are absolved from all Allegiance to the British Crown, and that all political Connection between them and the State of Great-Britain, is and ought to be totally dissolved."
"Tonight, I'd planned on sharing my testimony, but it's kinda been altered. Today, I lost a great friend. Philadelphia lost a great player. Jerome Brown died today."
Several of these occur at various points in one's personal life.
"We lost the baby."
"I want a divorce."
↑Thompson already knew the answer would be in the affirmative, as Butterfield had told the committee staff that already. But the viewing public didn't know, and the question seemed out of left field
↑ While well-known, actually a more accessible paraphrase. The real line was more like "Let w be the predicate: to be a predicate that cannot be predicated of itself. Can w be predicated of itself? From each answer its opposite follows. Therefore we must conclude that w is not a predicate."
↑Basically, it's an encoded form of "This statement is not provable in such-and-such theory". You can add that to the theory's axioms and create a new theory, but then there's an encoded form of "This statement is not provable in the new theory", and so on ad infinitum.