Security conscious software developers, certainly including .NET developers, should take particular note of the Metasploit Framework released into the wild by Metasploit. I have to stretch a bit to have faith that this information and toolkit will be used more for good than harm. Still, with all sorts of very nasty new viruses appearing, ones that can even hop from Bluetooth to your Symbian-enabled cellphone (see SymbOS.Cabir), all of us serious software professionals had better educate ourselves on the tools and techniques being used against us by the denizens of the Dark Side. Frankly, I think the virus wars have escalated beyond the coping ability of the normal anti-virus vendors and their products. From what I see, most organizations are absolutely clueless as to the new hazards we face today! If you care about your users, you will need to work very hard to protect them and your applications from the kinds of tactics demonstrated publicly by Metasploit and similar exploit information sources. May the Force be with you!