The journey from there to here
*Lincoln-Douglas

*Grant-Lee

*Monitor-Merrimack

*Sam Huff-Jim Brown

*Max Baer-Jim Braddock

*Shoeless Joe Jackson-Walter Johnson

*Bob Feller-Mickey Mantle

*Hamilton-Burr

*Boris Spassky-Bobby Fischer

*William Wallace-the English Army

*Robert Bruce-the English Army

*European swallow-African swallow

*Cinque-the crew of the Amistad

*Clarence Darrow-William Jennings Bryant

*Babe Ruth-Dizzy Dean

*Spinal Tap-The Rutles

I'm sure I have many more, but these will be good to start a discussion.

Comments
on Aug 27, 2004
At least you can still re-enact the Spassky-Fischer match....
on Aug 27, 2004
true...but it doesn't have quite the same feel, if you know what I mean...
on Aug 27, 2004
Fred Harteis vs....the world!!!!
on Aug 27, 2004
spc...but we can already see that!
on Aug 28, 2004
Otto Von Bismarck Vs. Niccolo Machievelli

Edit: I realize in hindsight you were refering to actual matchups that happened historically, rather than hypothetical matchups that would have been damn impressive to see.
on Aug 28, 2004
that's ok, history, I'll accept it. After all, I actually have two hypotheticals on the list (european swallow vs. african swallow and spinal tap vs rutles)
on Aug 28, 2004
Cal vs. Stanford 1982 in Football
on Aug 28, 2004
nice one, history...I might also add The Ice Bowl (although, living in Packer land, I've seen the replays of that many times, it's not the same as sitting out in Wisconsin's frozen tundra anticipating every moment).
on Aug 28, 2004
Maxwell V Gladstone would be an interesting one.
on Aug 30, 2004
If you accept hypotheticals:
Napolean vs Alexander the Great vs Ghengis Khan vs The Roman Empire

and a historical one:
the Battle of Trafalger (the British Royal Navy vs a combined French and Spanish fleet)