1947 : Congress investigates Reds in Hollywood [link] 1827 : Battle of Navarino [link] 1935 : Mao's Long March concludes [link] 1944 : MacArthur returns [link] 1973 : Sydney Opera House opens [link] 1774 : Congress creates the Continental Association [link] 1965 : End of an era at Volvo [link] 1819 : Union General Daniel Sickles is born [link] old War 1947 : The Red Scare comes to Hollywood [link] 1990 : 2 Live Crew members are acquitted of obscenity charges [link] 1944 : Natural gas explosions rock Cleveland [link] 1882 : Bela Lugosi born [link] 1930 : Sherlock Holmes debuts on radio [link] 1994 : Burt Lancaster dies [link] 1853 : French poet Arthur Rimbaud is born [link] 1803 : U.S. Senate ratifies the Louisiana Purchase [link] 1962 : Kennedy press secretary misleads press [link] 1968 : Fosbury flops to an Olympic record [link] 1964 : Relations between South Vietnam, the United States, and Cambodia deteriorate [link] 1973 : Watergate special prosecutor dismissed [link] 1918 : Turks send British officer to negotiate armistice terms [link] 1944 : U.S. forces land at Leyte Island in the Philippines [link]
Credit to This Day in History, by the History Channel (I get there emails, shoot me later)
32 new planets were found outside our solar system, 1 of the planets believed to be 8 times the mass of Jupiter, I only heard about this yesterday 20th of october but the story was printed on the 19th here the story [link]
I believe 20th October 1910 was the day the RMS Olympic was launched. She was the first of three ships of her class and the only one that didn't sink. The other two were the Britannic and their more famous sister ship, Titanic.
....do you mean historic events? o_O Then....how about Maria Theresa takes the throne of Austria on Oct 20th 1740 and since people were all "NO WOMAN SHALL SUCCESS THE THRONE WHEN IT SHOULD HAVE BEEN ME D<" the War of the Austrian Succession started too. :3 It can totally be useful to study history <3
Also...."Not really but the date looks very mysterious next year (at least in German version 20.10.2010)"