Note that this attack requires physical access to the DES chip, to stress it so it will fail. It works great against "tamper-proof" devices such as smart cards. It doesn't work against encryption happening at any distance from the attacker (e.g. across the network). It doesn't work against stored information like PGP-encrypted email messages either. However, it might be possible to use the attack by beaming disruptive energies (heat, electrons, microwaves, etc) at a computer which is doing a lot of encryption, while simultaneously monitoring that computer's activity across a network. John