World War I, World War II, the 1960's hippy movement in the USA, the Personal Computer, the Internet, Marilyn Monroe, Elvis Presley, JFK's assasination, Challenger space shuttle, landing on the moon, tons of great baseball moments...
I know these are mostly American related, I'm pretty ethnocentric I guess. Anyway, here are a few ideas.
That's the true harbinger of spring, not crocuses or swallows returning to Capistrano, but the sound of a bat on the ball ~ Bill Veeck