There are spider programs people have written to crawl through the internet looking for email addresses on webpages.  I have had websites since 1996 and know the frustration that spam causes as a result of your email address getting into the wrong hands.  This is my throwaway email address used when I purchase things over the internet, and even that could make you a target.  The new spam filters work wonders but I still don't like the idea of my server getting hit with that kind of traffic even if I see very little of it.  I know from experience, if you put an email address on a webpage it won't take long for that email address to be compromised.

The answer is, never put your email address on a webpage, use forms instead.  I will eventually do this.  Web forms allow people to type their message directly onto the webpage, click submit, and it is done; no email address is exposed.