"For work email, assume someone is reading your email as someone or something probably is," said Moorhead. "Most companies have filters that read every email, looking for offending words and images that don't comply with corporate standards."
Jones also noted that for most people sending illicit emails, they are going to be fairly easy to trace.
"You know, they could be texting too," he added. "If I were to cheat, I would be texting instead of emailing. Text message retention policies are usually very short -- just a couple of days with the provider.
"If you're cheating or threatening someone, email isn't the smartest tool to use unless you really know what you're doing," said Jones.
Sharon Gaudin covers the Internet and Web 2.0, emerging technologies, and desktop and laptop chips for Computerworld. Follow Sharon on Twitter at @sgaudin, on Google+ or subscribe to Sharon's RSS feed. Her email address is firstname.lastname@example.org.
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