FINDNULL

This program is based on the premise that nulls, unlike other characters
in a simple enciphered text, have no phonological properties that would
affect the frequencies of the characters around them.  The program scores
each byte in the text on the basis of how much the frequency of its neighbors
conforms to the average throughout the text.  The higher the score, the
more likely the character is a single uniliteral null.

This would not identify multi-character nulls, or nulls which are only null
under certain circumstances.

findnull.cpp -- This is the source code
findnull.exe -- This is the compiled program

The source is distributed for free, with no warranty as to fitness for
a particular purpose, and no obligations are binding on anyone who wants
to use it or modify it.  Just remember me when you're rich and famous.