Image him and JackDeanTyler in a thread!
If we’re going to have John Lennon, then George Harrison should be here too. What a Pit Thead that would be.
Maybe Jesus could answer the big Question: What Would Jesus Do for a Klondike Bar?
Nimrod - what a Pit thread he could make. Plus, hunting tips! And TMI about doing his Mom.
Bezalel - master wood worker, should be good in all those home improvement threads.
Mahershalalhashbaz - Trek Doper!
Hannaniah, Mishael, and Azariah (aka Shadrak, Meshak, Abednego) - politics and religion in GD
Jonah - I bet he would Pit a lot.
Jesus - just what would he do? Should be pretty good in GQ, too. “Well, as the Son of God, I’ve found that…”
Paul - debates, both in the Pit and GD, plus, a regular poster in CCC and CSR.
But wouldn’t people get up his face for posting anecdotes instead of data?
Another vote for Oscar Wilde. And Mark Twain, Ben Franklin, Einstein, MLK, and Dr. Seuss, Fo Sho.
Yeah, I’m sure some would.
But, as we’ve discussed before, sometimes anecdotal evidence trumps innaccurate or incomplete cites. Depends on whether you trust the poster as to whether you accept their anecdotes.
Besides, couldn’t he just manufacture the data?
“Hey! That wasn’t in my physics book before! I’ll see you in The Pit!”
“Yes. Yes you shall…”
As Nietzsche might say were he an SDMB member, to become truly great a poster must move beyond worrying about being banned.
But it would be his insistence that Cecil Adams is Dead that would really tick people off.
Might be nice to have Michael Moore here, so he could just start an “Ask Michael Moore” thread and have done with it. But there would probably still be umpteen Pit threads about him.
Hate to say it- but I’m not sure that account has any history further than Alexander Hislop’s THE TWO BABYLONS. Which I’ve been meaning to ask about on the SDMB anyway S
Voltaire
E.B. White (dunno if he counts, but what a poster he’d be!)
Any pope, really.
Hmmm…better than that – the Jesus of the Apocryphal gospels would prob just frizzle anyone who dared to contradict him…
Johnny Bravo
My ‘pope vote’ would be for Innocent III, whom I once referred to as the ‘Phil Niekro of the Papacy’…
Here’s my thoughts:
Andy Kaufman
I’ve always been a fan of Marcus Tullius Cicero, I know some love him and some hate him, but I think he’d be awesome in Great Debates and the Pit simply for his ability to verbally knock the shit out of someone.
As for Presidents: Cool Cal
Samuel Johnson: I could see him holding his own in Great Debates, Cafe Society, or the Pit (“Sir, you are a scoundrel and an asshat.”)
G. K. Chesterton, George Bernard Shaw, H. G. Wells… Ah, there were some Great Debaters in those days.
Montaigne.
After reading Shirley Jackson’s Life Among the Savages (which is a bit like an edgier Erma Bombeck), I’d love to see what she would contribute to MPSIMS.
Lewis Carroll.
And I second some of the others already mentioned, particularly Ben Franklin, Mark Twain, and Isaac Asimov.
Sir Arthur Conan Doyle would post a lot on every message board but he’d get his facts wrong and leap to improbable conclusions. He’d also hijack every post in Great Debates and turn it into a thread on spiritualism. I also suspect he would give up and leave the SDMB, but he wouldn’t be able to resist coming back…
Andy Warhol would have the highest post count but he would only cut ‘n’ paste from his previous posts.
Socrates would post in Great Debates, but he would get banned for posting under a number of ‘sock puppet’ accounts as he tried to supply the necessary set-up lines for his own devestating rebuttals.
Vincent van Gogh would post frequently in Cafe Society but nobody would appreciate him at all until he left the SDMB, when everybody would say what a genius he was.
Groucho Marx would be scathingly funny and misanthropic, as in his later years, but eventually he’d just get tired of posting on the message board and spend his time in the #straightdope chat room unless something really interesting came up.
e e cummings would give up on the SDMB because everyone would rag him about punctuation and capitalization.
Carl Hiaasen would post about a variety of topics but he’d always have to work into every post that it was somehow about Florida.
William Shakespeare would post on the SDMB, but everyone would suspect that he’s actually a screen name for Francis Bacon (who had a promising position as the mod of GQ until he began to play favorites with doling out punishment).
James Joyce would be a regular and treasured poster in MPSIMS, like Rue deDay, but every time he posted in someone else’s thread it would turn into a rambling hijack.
Michael Moore would be a regular on the SDMB but he would keep posting his political views in the wrong forum.
What? Innocent III used to through spitters?
AT LEAST HE WOULDN’T POST IN ALL CAPS.
Phil Niekro of the Papacy, not Burleigh Grimes! 
What I meant in my paper was that Innocent III took on just about every head of Europe and no one could touch him – at the time I admired the knuckleballing Mr Niekro tremendously.
My uni supervisor despaired of me, really.
PS I know the suggestions are limited to historical figures, but, crikey, I would like to see John Lowenstein join up.
Also, I’d like to have Schroedinger back so I could ask him if he actually owned two cats and was just pulling our leg. http://www.straightdope.com/classics/a1_122.html
My three immediate thoughts were Schroedinger, Ben Franklin and C.S. Lewis.
Others I’d like to see:
Archemedes
Gauss
Augustine
The apostle Paul
Voltaire. (My money’s on Paul for that one.)
Leonardo da Vinci
Hilbert
Godel
M C Escher
And just for the fun of it, Peter Jackson.
John Locke.
Eleanor of Aquitaine.
It might be interestering to get Isabella of Spain, simply to watch her get flamed for her anti-anything-non-catholic views. She would recieve some sympathy because of her daughters, though.
Elizabeth I.
Cleopatra.
I know that this isn’t an actual “historical” figure yet, but Dubya- I think it would be amusing to watch him form nonsensical answers to our criticisms.
Emperor Nero- Let’s hear the perspective of the crazy guy who drank a bit too much out of lead cups.
I agree about Shakespeare- we can always use another person who can write in a thoroughly entertaining manner, even though his stories do often seem a bit repetitive.
If Troy actually did exist, as is thought now, I would really like to be able to talk to one of the lower servants on the royal household there, one who could kind of hear everyone’s conversations and not be noticed, to find out what really happened.
And hey, assuming His/Her/Its existance, why not God, too?
Actually, scratch that idea. If we had some unquestionable authority here to tell us the answers to all of our questions, GD wouldn’t be nearly as much fun.
Well, as long as we’re going to have some political flamewars going on…
I’d like to see Richard Nixon and Pierre Elliot Trudeau, mano-a-mano on world politics in the Pit.
Well if **Jesus ** joins the SDMB I can envision the longest thread EVER: ‘Ask the son of G-d’. His signature? ‘What would I do?’
I’d like to see Nero here, he’ll be banned pretty quickly, but think of the entertainment.
Christopher Columbus would make a nice addition, and if we get Erik the Red to join (I’d his membership fee) we can settle the matter of the discovery of America right away.