http://www.csc.ncsu.edu/~brabec/antispam.html :
Protect Your Webserver From Spam Harvesters
This might be of interest to those of you with the ability to do some
configuration of your webserver.
I was browsing the log files on our webserver the other day and I noticed
a browser name I hadn't seen before: "EmailSiphon". As you might guess,
that's the ID of a program that spammers use to harvest email addresses
from your webpages. With a bit of research I found some of the most
popular (based on availability on the net) email collectors on the net,
and determined the browser ID that each uses.
It lists several of the big mail-harvesting user-agents. If you run
Apache, and you have email addresses on your pages, and you don't want to
get those addrs spammed, it might be worth adding the mod_rewrite code
listed at the bottom of this page.
--j.
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