How effective is @ sign substitution to prevent email harvesting?

Complete waste of time, or moderately effective?

[Jeremy_H]

I'm sure that the prevention of email harvesting has already been discussed to death, but I'm wondering...

Short of creating a whole new form submit page, or using images, or javascript...

How much coverage do you think substituting @ for @ in the email address be?

Completely ineffective and a complete waste of time? Or maybe it's moderately effective and worth the couple of seconds it takes to substitute?

[DanA]

As for me almost completely ineffective.
email harvesters keep on asking for the pages where @ has been substituted for more than a year.

[Jeremy_H]

Thanks for the reply,

Any thoughts on if the complete email address was subsituted with &#XX; characters? Or maybe just the domain name part?

[DanA]

You can use unicode, then select your encoded text with Mozilla, then view selection source.
Any robot can do the same and decode on the fly.
If you need clickable email addresses with almost any browser, javascript encoding seems to be the solution.
If you just want the addresses to be seen there are a few css solutions (for recent browsers).
If the user has to type the address, robots use commentsatsensisdotcomdotau, guys dot nl, at girafa dot com, I even found a harvesting specialist using the html: addr<unexisting tag="">ess</unexisting>

[fabricator]

I use javascript to generate the mailto: link for my own site. Very few spammers actually send to that email address, its only the ones who visit my site in person that can read it.

basically do something like:

var username='me';
var domain='example.org';
document.write('<A href="mailto:'+username+'@'+domain'+">email me</A>');

Change the var names around at will just to keep things random and harder for bots.

the spambots can't figure out there is a email address in there. Another further trick is to put your address as an image rather than plain text.

[Dijkgraaf]

I use JavaScript to write it, but among other things I do the the document.write by calling a function that is in an external javascript file. That way there isn't even an mailto: or an @ found anywhere in the page itself so even less chance for a bot to find an e-mail address.
I've never had any SPAM to the address I've got an my website protected this way.