"Dogs and cats living together, mass hysteria!" - Dr. Peter Venkman, Ghost Busters.We're not quite there yet, but some curious developments emerged last week regarding Windows, Linux and Macintosh interoperability. The big news was Apple's announcement of a dual-boot Mac\/Windows XP. Then there was the launch of Microsoft's Linux\/open source Web site. Yes, you read it correctly; it's not a sentence-long typo.This site, announced last week at LinuxWorld, is the official portal\/blog for Microsoft's open source interoperability initiatives. The site is run by Bill Hilf, who is in charge of the Linux and open source lab on the Redmond campus. Named for the protocol port for e-mail servers on the Internet, Port 25's goal is to give updates on Microsoft projects aimed at making its software compatible and interoperable with Linux and open source applications.By now, you've probably seen Microsoft's other Linux-related Web portal, where the software giant aggregates all the studies, surveys, white papers and other materials that point out the lack of cost savings and complexity in moving from Windows to Linux servers."The great thing is that as a market we've gotten past the David and Goliath stuff," said Hilf during his LinuxWorld keynote last week, regarding Linux\/Windows relations and interoperability efforts. When Microsoft puts as much marketing muscle behind Port25 as it does GetTheFacts, maybe that will be true.