[csee]

Are they observer independent? From the article:

  "Of course it is simplest to build a computer where the high voltage states correspond to 1s and the low voltages states 0s or vice versa. But there is no requirement that we build our computers that way. We could build a perfectly valid computer where the high voltage states of even valued registers correspond to 1s and where they correspond to 0s in the odd valued registers, or a computer where the mapping flips on every 13th clock cycle. The system only “computes” because of the way we have encoded information."

[xg15]

This might work as long as your computer doesn't have any IO. If your computer operates your garage door, I wish you good luck opening the door through the power of imagination.