Tina Fey and Amy Poehler - because they are two of the greatest Comedy actors of all time, male or female in my opinion. If you are not familiar with these two ladies I highly advice checking out "30 Rock" with Tina and "Parks And Rec" with Amy. Both of them shows are hilarious, the Comedy is less than traditional at times but these two execute it perfectly.
Benedict Cumberbatch and Louis C K - the clever meets the stupid, the serious meets the joker. I know this seems like very much a miss match of talents and work, but if you ask me you can say the same thing about Melissa McCarthy and Sandra Bullock but that worked well. I think their both vast differences would make for a great on screen relationship.
Kevin James and Patton Oswalt - purely based on their relationship in "The King Of Queens" not saying that they are not as good solo. However, their work together as Doug and Spence on King Of Queens is easily one of my favourite relationships in sitcom history.
Chris Pratt and Andy Samberg - Pratt and Samberg are from the same style of Comedy they both rely heavily of the silly/idiotic persona which for me they pull off very well. I.E their roles in "Parks And Recreation" and "Brooklyn Nine-Nine" respectively, their both reliance to work on the sillier Comedy might become a bit tedious but I think that these two would have a great repartee.
Anthony Mackie/Michael Ealy and Bradley Cooper/Mark Wahlberg - maybe a Lethal Weapon reboot? The younger black man actor who can pull off Comedy and Drama was a bit of struggle for me, I was stuck with these two and these two alone on the other hand the kind of insane tough guy who is funny but can portray emotion too there is like 7 billion ha. However I think any combination of these four actors would work well together, Ealy was brilliant in "Almost Human" and the same goes for "Winter Soldier". Cooper kind of played a Riggs sort of character in "A Team" and the same could be said about Wahlberg in "Pain & Gain". Plus all four are pretty accomplished actors in their own rights.
Charlie Day and ANYBODY - This guy is hilarious he is stand out funny in "It's Always Sunny In Philadelphia" which he leads 4 other great comedy talents, he was also the only good part of "Horrible Bosses" in my opinion.I would love to see him bring a character like Charlie Kelly to the big screen along side anybody else I think the insanity, vulgarity and down right stupidity would be a match for ANY character along side him.
Sir Patrick Stewart and Sir Ian McKellen - Now for the pièce de résistance, is there a truly better combination in the world right now than the great Sir Ian McKellen and Sir Patrick Stewart. These two dudes are currently entwined in what can only be considered THE GREATEST BROMANCE OF ALL TIME and if you disagree even one iota you're wrong ha.