So, can anyone point me at any appropriate modules? Or at an algorithm that I could turn into a module?

Greetings Fellow Monk!
I did some digging on CPAN and found a few related modules that I thought that you might find of interest/use. I have listed a few that immediately caught my eye below along with thier brief CPAN description:

• Statistics::ChiSquare -- How Random is your data?
• Math::Random -- Random Number Generators.
• TrulyRandom -- Perl interface to a truly random number generator function.
• Data::Random -- Perl module to generate random data.

In addition, a general CPAN Search on the term random yields some interesting possibilities.