#!/usr/local/bin/zsh
X='write your own rand function ;o)))'
Y='write your own rand for something like this aa:bb:cc:dd:ee'
DREAM_TIME='how long should I sleep?'
while true
do
ifconfig msk0 inet 10.0.0.X link 00:Y
sleep DREAM_TIME
done
After executing this code you will probably end in hell with interface connection, but ... just try it ;o)