Philip Zimmerman (who you may know as being the creator of PGP) has announced Zfone, a seamless PKI-free, Diffie-Hellman hashing, man-in-the-middle-detecting SIP VoIP client. So, if you're worried about your VoIP traffic being sniffed, you need worry no more; not to be confused with his mid-90s encrypted VoIP product, PGPfone, today's encrypted VoIP brings Internet anti-wiretapping up to date with the latest in SIP and RTP protocols, as well as OS X (and Linux) support (sorry Windows peeps, you're out of luck for now).