I'm no longer convinced that "safe" computing practices are enough anymore. The Flashback trojan alone is estimated to have infected 1% of all Macs out there. In contrast, the Conficker botnet, which is the biggest malware attack on Windows to date, infected a lower percentage.

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The problem with the Flashback trojan is that people were unwittingly infected by going to sites that themselves were compromised. Not shady or disreputable sites… places like WordPress. If you visited a compromised site and were susceptible to the vulnerability in Java, you too were compromised, invisibly. Period. The days of telling people to be smart and use "safe" computing practices are over. Most people grossly overestimate their ability to judge what is safe anyway.