Important Digital Cash Question...

[Simon Spero]

Ok. So we've got Alice and Bob trading their cash back and forth, with 
Mallet trying to steal their cyber-dosh, and Eve listening to their 
conversations- this leads me to the big question:

What's the right name to use for the Banker? I've been using "Nick", 
after Nick Leeson; any other suggestions?

Simon 
---
(defun modexpt (x y n)  "computes (x^y) mod n"
  (cond ((= y 0) 1) 	((= y 1) (mod x n))
	((evenp y) (mod (expt (modexpt x (/ y 2) n) 2) n))
	(t (mod (* x (modexpt x (1- y) n)) n))))