Here are various implmentations of RadioGatun[32], including
a couple of C-language implmentations, two Javascript implementations
(one that uses Document.write, the other that uses DOM to output
the test vectors), as well as a C++ implementation.

These programs are open-source, and are released to the public domain. The
program is called "rg32hash" and is used like the md5sum program. Unlike
the md5sum program, this program automatically recursively enters
directories. Give it the file name or directory name you wish to hash,
and it will output on the standard output the 256-bit Radio Gatun 32-bit
hash of all of the files you list. If you want to perform a recursive
hash from the current working directory, simply type in something like
rg32hash . > RG32SUMS

I have both a Windows 32-bit binary and *nix source code of this program
available.

ref-unix.tar.bz2 is a *NIX version of the Radio Gatun reference code and 
test vectors.

rg32.cpp is a small C++ class that implements RagioGatun32

rg32-bin.c is a small C program that outputs a RadioGatun32 binary stream
on standard output.

small_du_for_windows is a Windows program that, in addition to having a 
(large file size compatible) version of "du" (called "sd"), has a similar
program that provides both the RG32 hash and the size of files and folders; 
I made this program to compensate for MSYS' lack of the "du" command.