eMailTag is a very simple Zope product.
It is actually just a Python script with a very specific purpose -- it generates e-mail tags for use in HTML (both anchors and links). What makes it useful is that it obfuscates the actual e-mail addresses in the tags using a simple algorithm that baffles spambots but which browsers can see right through.
Thus, your resulting web page will look normal to its intended audience (no matter which browser is being used) but will hide e-mail addresses from spambots. As simple as the obfuscation is, there are currently no known spambots that can see through it (although it's still a good thing to configure your server to send spambots away if you can anyway -- both approaches work well together for a more comprehensive anti-spam solution than either alone).
<dtml-var expr="eMailTag([email protected],The BigWig,InfoPlease,e-mail me)">
[email protected]
The BigWig
InfoPlease
e-mail me
<a tal:replace="structure here.eMailTag([email protected],The BigWig,InfoPlease,e-mail me)" href="target">target</a>
<dtml-var expr="eMailTag([email protected],The BigWig...,Author,HTML link)">
The BigWig...
Author
HTML link
<link tal:replace="structure here.eMailTag([email protected],The BigWig...,Author,HTML link)" />
Note that it works properly with Page Templates; it bypasses the weird ZPT bug (mentioned at the bottom of the ZPT FAQ, see Comment #11) with how ZPT turns all & characters into & sequences even if they are already part of escape sequences by simple virtue of being a script.