OK, I have tried doing a search on this and so far have not found what I want. I once had bookmarked, and then lost, a website that had a calendar containing the birthdates of a humongous amount of people, so that if you wanted to find out who shares YOUR natal day you could impress them. There are several sites I have found, but most only have half a dozen or so for any given day. For example, I know that Anthony Hopkins and John Denver(ugh) share my day, which is December 31st. But the site I remember, and can’t for the stupid life of me find again, had a couple dozen. This site din’t go with just current celebrities, but had historical figures from at least the last five hundred years. I am going to keep searching, but if anyone could give me a hand I would appreciate it.
I’ve seen them here on IMDB’s “on this day” page.
Hope that helps a bit.
Leanne’s Celebrity Birthday Database
History Channel - This Day in History (Click on More of Today’s Headlines)
Scpoes Systems - Any Dayt in History (Good material but slo-o-o-o-w loading.)
Congressional Birthdays this Month
Yahoo - Index page for Birthday related stuff
Yahoo - Today in History (Selectable date appears limited to current month.)
I dunno if I count as famous, Baker, but I share your birthday. 
So does Val Kilmer, Henri Matisse, Ben Kingsley, Diane Von Furstenberg, and Donna Summer.
LifeOnWry, how much before or after 1954 were you born? And does it bother you that we share a birthday with John Denver(shudder) I mean, I don’t mind Hopkins, Kingsley, or even Kilmer, but DENVER! Ack. Thanks for the replies everyone. So far they aren’t the one I had, but theres some great stuff I hadn’t seen before that I have had fun looking at.
Exactly ten years after. At 1:15 PM CST.
Also, The Internet Movie Database has a page for finding out what happened on a particular date (births, deaths, movie releases, etc.) within the realm of the movie business.
I myself share a birthday with Julia Roberts, Daphne Zuniga (Spaceballs), Annie Potts (Designing Women), Telma Hopkins (Tony Orlando & Dawn), Joaquin Phoenix (Gladiator), Andy Richter (Conan O’Brien’s former sidekick), Lauren Holly, Bill Gates, Dennis Franz (NYPD Blue), Michael Crichton (writer of Jurassic Park)…
ATM, I can only remember one celeb b-day I share with…
Bill Clinton… (and you thought John denver was ugh)
which, incidentally, is August 19th
I share mine with George Bush, Sr. and Anne Frank.
June 12.
Glenoled, you also share with Orville Wright, Alfred Lunt, Ogden Nash, Gene Rodenberry, Bill Shoemaker, and Coco Chanel.
I share a birthday with Joe DiMaggio, Ricardo Montalban, John Larroquette, Amy Grant & John F. Kennedy Jr. exactly, and Christina Applegate.
I once, at the same time, dated a guy whose birthdate was the same as mine(one year earlier) my neighbor across the street(15 years earlier) and my dad’s car saleman.
I share one with Tina Turner(Nov. 26) Mick Fleetwood, I think also.
My birthday is today!!! I know you all care immensely 
Lorie
Moby(the musician) shares a birthday with the 9-11 disaster. Man, if that guy wasn’t meek enough as it is.
I share a birthday with the lovely Gwyneth Paltrow, also Mira Sorvino, Moon Unit Zappa, Janeane Garofalo, Ben E. King, Brigette Bardot, and Ed Sullivan.
I was born on the same day as…
AWB
Is that you, Mr. Richter? How’s life without Conan? :D:D