Batman and Robin?

David and Jonathan

Peter and Paul

Samson and Delilah

Oh, pooh - I was trying to think of them.
Charles beat me to it, so I'll have to make do with...
Abbot and Costello

Byrd and Tallis

Cosmas & Damian
Cain & Abel

Sergius and Bacchus
Boris and Gleb
Saints Medard and Gildard

Cyril and Methodius

Benedict and Scholastica

Captain and Tennille?

A few come to mind:

Sonny and Methodius
Cain and Stimpy
Starsky and the Bad Thief

Bob and Ray
Martin and Lewis
Opus and Bill the Cat

Mary and the Child Jesus. Very iconic.
St. Joseph and the Child Jesus. Almost as iconic.

Somewhat less iconic...
Moses and Elias

Even less iconic ... but still iconic
Gilbert and Sullivan
Dick Van Dyke and Mary Tyler Moore

The coyote and the road runner (well I guess they were kind of at odds but)

Elmer Fudd and Bugs Bunny
Barney and Fred
The Smothers Brothers
Ricky and Lucy
Ethel and Fred
Sonny and Cher
Tom and Jerry
Ben & Jerry
Felix and Oscar
Han Solo and Luke Skywalker

should I go on?

Lone Ranger and Tonto
Mutt and Jeff
Jacob and Esau
John and Charles
Sylvester and Tweetie
Mickey and Minnie
Daisy and Donald
Ed Mcmann and Johnny Carson
Dave Letterman and Paul Schaffer
Monica and Augustine
Cheech and Chong
Laverne and Shirley
Kermit and Miss Piggy

shall I go on?

Adam and Eve (need I say more?)

shall I go on?

Francis!
Oh, please don't!
_______________________________


Yin and Yang

Pins and needles

A rock and a hard place

Scylla and Charybdis

Mason and Hamlin

Peas and carrots

Dr Jekyll and Mr Hyde

Upstairs and Downstairs

William and Mary

Eggs and bacon

Hue and cry

Wailing and gnashing (of teeth)

Goulding and Wood

Taylor and Boody

nuts and bolts

peanut butter and jelly

far and away

man and wife

bangers and mash

Pyramus and Thisbe

H___ and high water

Simon and Schuster

Pro and con

Harrison and Harrison

Pastrami & Swiss (on rye)

To be or not to be

Joachim and Anna

Alpha and Omega

Briggs and Stratton

Currier and Ives

Show and tell

Give and take

Spaghetti & meatballs

Steak & potatoes

Fish & chips

Hollywood & Vine

Monitor and Merrimac

Lincoln and Douglas

Post and lintel

Spic and span

Spit and polish

... over and out

Dolly Parton.

Stimson for the win!

Ahem.

enough and more than enough. ;-)

death and taxes. Amen.

I haven't seen any one mention up and down, left and right, in and out, or Green Eggs & Ham

alpha and omega

agh... Charles already got it

love and marriage
horse and carriage
Alphonse and Gaston

Charles and purple.