I need to creat a field based on another field (numeric) that is the numeric value in words. 

For example if the numeric field is "2" then the new field would be "two", "315" would yield "Three Hundred and Fifteen".

What is the best way to go about this?  I'm not looking for an algorythm here, I already know how to code this.  I'm looking for a way to implement it in SalesForce.

Formulars don't have loops or vaiables, so it looks like that would be very difficult to code.  Is there a way to do this in perl (that's what my original code is written in), or python, ruby, or even C?  

Where should I look for this?  Is it alredy implemented?

Matt