Up until now Mac owners have been relatively safe (and smug) when it came to the infectability of their computers. Worms, trojans, viruses, and other malware were considered to be primarily the domain of Windows. That may have changed last week, however, when the Russian security company, Dr. Web, reported that as many as a half a million Macs are already infected with what is being called the “Flashback Trojan”. Here’s how to know if you have Flashback Trojan, and how to get rid of Flashback Trojan.