In case you haven't noticed I'm liveblogging Black Hat 2007. I just watched the end of Phil Zimmermann's talk about his new VoIP encryption product / SDK: ZPhone. Z-Phone is an application that allows you to make secure, encrypted phone calls over the internet using standard VoIP protocols. As with Zimmerman's other well known project PGP, the source code and software is given away for free.
During the question and answer session he talked about his disdain for software patents, but added that he had recently applied for a patent for the ZPhone protocol, with an interesting twist. He is using the patent for good, and here is how: Part of the patent states that any time a key is copied and stored (which would allow a party to monitor / wiretap the call) a flag is set on that session that designates the wiretapping. This won't prevent interested parties from not using the flag, but it will prevent them from using the free license for ZPhone and thus force them to disclose that their product is wiretap friendly.
Here are some photos from the talk:
I just heard this random quote in the press pen: "Our experience is to stay off the wireless network at Defcon, we actually got hacked into a few years ago." I bring my own out of band connection with me to all security conventions and even with that I still do all my surfing / blogging / emailing through an ssh tunnel to a trusted server.