IIRC the -0.00 representation happens when you're using sprintf("%0.2f",$some_number_very_slighty_less_than_zero). The last two digits happen because they were specified in the format string. the minus sign is supposedly because that's how the C stdio lib does that.

update: 

#include "stdio.h"

int main() {
  printf("%0.2f\n",-0.000000000000000000000000001);
}

[download]
$ ./a.out 
-0.00

[download]
"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re^2: Why is Zero not 0? by Joost
in thread Why is Zero not 0? by jluther

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