Over a year ago, I wrote a couple of programs that use the 32-bit version of the Radio Gatun cryptographic hash to calculate the cryptographic sums of files.
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.