TechCrunch reported this morning that Google has bought Gizmo5 for $30 million. Gizmo5 is a SIP-based Internet phone service that competes with Skype. Such an acquisition would make sense, given the already-close relationship between Google's Voice service and Gizmo5. One little-noticed effect of that relationship is that the combined services already allow free inbound and outbound calling to and from the PSTN via Internet-connected PCs with headsets. A formal acquisition would presumably make such calling even easier.