There's a CD sampler by a HiFi manufacturer who also runs a record label (Naim) where all the tracks were recorded onto two mics feeding a nagra reel-reel recorder. No mixing, no EQ, no nuffink. Called True Stereo I think.
The engineer worked out the levels by placing the vocals/instruments different distances from the mics.
Most of it isn't my sort of music, but the feeling of being there is incredible, even through an ipod with reasonable headphones. Wouldn't work for a commercial recording, and also probably wouldn't work for a lot of music styles, but as an exercise in what recorded sound can be like, it's very good.