One Way Network Connection

view full story

http://serverfault.com – I have a very paranoid client who runs two separate networks (one offline, one online) with separate PCs etc. I have a challenge in that I have written an application for them that will run on the offline network however the network needs to be able to send emails to clients. My idea is to have a one way network connection (like a diode) from the offline server to an online PC that would send the emails. What is the most effective way to go about this that is semi cost effective? Can I get a one way network card? Windows Server 2008 Network, Windows PC. (HowTos)