I cannot think of any (my friend Jason likes to point out that Jefferson and Adams died on the same day). I did a little research and came up with these,
Sam Kinison and Kim Basinger
the 3fer WKRP's Tim Reid, Paleontologist Richard Leaky and guitarist Alvin Lee
John Denver and Ben Kingsley
Condi Rice and Yanni
the 3fer of Lorne Micheals, pitcher Tom Seaver and Danny DeVito
Amy Grant and JFK, Jr.
Chevy Chase and RL Stine
Lenny Bruce and Margaret Thatcher (guy that got people cussing and the Iron Maiden)
Mike Ditka and Lee Harvey Oswald (3-4 defense and guy that stopped Camelot)
3fer of Pat Sajak, Hillary R Clinton and Jacklyn Smith of Charlie's Angels
Peter Jackson of Lord of the Rings and U2's Larry Mullen, Jr.
Tommy Lee Jones and Oliver Stone
David Copperfield and Mickey Rourke
Lynne Cheney and David Crosby- proof against Astrology
Nomar Garciaparra and Monica Lewinsky (the guy that got traded and broke the curse and the girl that almost brought down a president)
Roger Ebert and Paul McCartney
Alex Keaton's "parents" on Family Ties were born same day... weird
Edward VIII and Alfred Kinsey (guy that gave up throne and father of modern sex research)
Ed Norton and Christian Slater (plus the guy from Everlast)
the closest we got, but no where near is: Sigmund Freud and Richard Peary (North Pole explorer)
But all pale in comparison to the (1) father of modern science that changed everything about the way we look at the world and (2) the man that saved the greatest political experiment in human history from implosion while freeing slaves and pushing America towards the greatness it had claimed in the Constitution and Declaration of Independence (finally beginning to live up to its hype- but a long way to go). Both were brilliant, timeless writers that are unparalleled.
Newsweek has an article asking the question I thought of this morning. Who is greater? Who is more important or influential? Who had a greater impact upon society or changed the human trajectory more?
I have thought about it and could comfortably argue either position. Newsweek asks (on the final page of 3, "what might have happened if neither had been born?,") which tips the scales to Lincoln. However, in terms of influence, my mind leans towards Darwin, but my heart lies with Abe, especially with our new president.
I was born on the exact day as Jorja Fox, former star of CSI.. Does that count?