'Doug Elrod' via World News Now Discussion List writes:
> Thirty-One is one of those "Interesting Odometer" numbers, "11111",
> if you have a binary odometer ;-)
>
> It's the last number you can represent on one hand, by extending
> fingers to represent ones, using the thumb for the high order bit.
> Others may think you're saying "five", but the WNN cognoscenti will
> know you can only mean *31*!
It's only the number of bits, not the ordering, that affects the
largest number that can be represented by that many bits. Use your
pinkie for the most significant bit if you want. Or your middle
finger. "I got your most significant bit right here!"