The The Center For Democracy & Technology has released an interesting study of where spammers get e-mail addresses (it’s a 16 page PDF). It offers some fairly practical tips on cutting down on likelihood of your address being trapped by address harvesting apps. The best advice is to simply replace the “@” in your e-mail with word “at”, so that “[email protected]” is written as “example at”. This seems to fool all e-mail harvesters but after a moment’s thought is intuitive to most humans.