solution: http://pastie.caboo.se/144096

specs: http://pastie.caboo.se/144098

Nothing particularly CS-y about my solution.  I just started with how I 
know to make change from my days in retail and added complexity as more 
examples came in.  Of note, is the fact I wrapped it in a class.  That 
was done to make heckling and flogging the code easier.

--R