Memory efficient opening repertoires

By memory efficient I don't mean the best repertoires, but the ones that require the least memorization because:

a) you play openings for both colors

b) the openings easily transpose to each other

What's yours?

Here's my take ...

BLACK ("e6 against everything")

e4,e6: French defense

d4,e6,e4,d5: French defense by transposition

d4,e6,c4,f5: Dutch defense but without the Bg5 line and Staunton Gambit

WHITE

f4: Bird's = the reverse of the Dutch

Regards to all

King's Indians. Simple, will be moderately playable against anything, and you don't even really have to look at your opponent's moves.

 Even against 1:e4 ?

 I'm no expert, but in blitz I premove Nf6. If white plays e4, then it's the Alekine's defence. (1. e4 Nf6)

Sorry I didn't specify, I'm talking about chesscube.com where the time starts as soon as white moves. (or instantly in a tournement)

The Alekhine and the English sorry but it is so easy, that is pretty much my repetoir except when i feel adventurous and play the Italian or other hypermoderns like the KID or the KIA or Nimzo Larsen

kings indian is full of variations.. and playing d6 against e4 is pirc defense, it can  lead to either "King's indian pawns structure" or "dragon pawns structure" it depends on the variation you will use, and these structures are making some complix middle games.

Better for blitz to play simple moves, may be as white play colle system.

and for black you can play semi-slave against queen's opening.

against e4 you may like to try center counter defense.

those i said are easy to remember, and simple games.

I think alot of the people in this thread is going down the wrong road. Chosing d6 against both e4 and d4 hardly leads to nontheoretical positions. It leads to a mass of extremely thick theory and razor sharp variations.

It's rather fun how alot of the "I don't want theory" choses the same first move against all white's first move, even if it leads to completely different and theoretical positions. Is your problem with theory really remembering the first move you do on the board?

 +1

I suppose many Sicilians will play the English opening too is it true?

I have a good friend who is an IM but plays at the GM level, and he can play both English and Sicilian.

The purpose of combining openings like "English with Siclian"

"Caro-Kann, with the London system and Slave"

"Kings Indian Defense, King's Indian Attack, Pirc," and so on.

It's not that they have the same openings, but they have the same pawn structure, so they have similar middle and end games.

I tried that road briefly, and it just didn't seem to work for me. I've lately been going about learning main lines and then every OTB game I play I try to learn one more position/move/idea from what I knew before. I honestly think that ends up being pretty efficient.

Yeah I play both sicillian and English, KID and KIA and the KG and a few other gambits

Reti Opening Works as white and so double fianchetto

There is some logic in playing reverse systems.
There is also some logic in playing similar defences against 1 e4 and 1 d4.
It allows you to accumulate experience with the resulting positions faster.
French, Dutch, Bird.
Classical French, Queen's Gambit Declined, Queen's Gambit
Pirc, King's Indian Defence, King's Indian Attack.
Winawer, Nimzovich Indian Defence, Larsen.
Caro-Kann, Slav, London.
Sicilian, Benoni, English.
Accelerated Dragon, Grünfeld, Catalan.

Reti (1. Nf3) as a waiting move so white can essentially choose which opening they play is a good choice, (e.g. you really hate Sicilians, instead of playing 1. e4, where 1... c5 is the most popular move, play 1. Nf3 where 1... c5 is the third most popular move, and if 1... c5 does get played, you have the option of playing a Symmetrical English instead). 
As black, 1... Nf6 seems solid against literally everything. e4? Alekhine's. d4? Indian. c4? Anglo-Indian. Nf3? Transposes into Indian, Anglo-Indian, or KIA.