Thoughts on spam control

I saw an interesting link suggested in this group for the spam problem:
  
http://www.e-scrub.com/wpoison/

From there I saw this program.

http://www.e-scrub.com/cgi-bin/deadbolt.cgi/show_demo_entry

  These are both interesting programs, but may have inherent problems.

wpoison: Traps e-mail web crawlers, but what is to stop it from trapping
          other web crawlers that altavista, webcrawler, excite, yahoo and
          other people use?
          
          It boasts that it can provide an almost infinite number of bogus
          e-mail addresses as well as hyperlinks. (these hyperlinks point
          directly back to the same page) Why would you want to trap a web
          crawler on your site, using your bandwidth and resources almost
          indefinitely?

Deadbolt(tm): This filters out known e-mail spammers, from an automatically
               update-able lists, provided by E-scrub Technologies. What
               happens when a majority of ISPs are using a filter like this and a
               legitimate e-mail address is accidently put in the list?
               That e-mail address would then be denied by a majority of the
               ISPs.

wpoison: Traps e-mail web crawlers, but what is to stop it from trapping
          other web crawlers that altavista, webcrawler, excite, yahoo and
          other people use?

It uses an anti-robot meta tag:
<meta name="ROBOTS" content="NOINDEX, NOFOLLOW">
so the idea is genuine, well written robots will stop after hitting it
once, but the address harvestors hopefully have no concept of the above
tag and keep hitting.

I downloaded it last night and really like the idea.

          It boasts that it can provide an almost infinite number of bogus
          e-mail addresses as well as hyperlinks. (these hyperlinks point
          directly back to the same page) Why would you want to trap a web
          crawler on your site, using your bandwidth and resources almost
          indefinitely?

I thought about this almost immediately. First thing I did was hack in
a delay. If they're going to get caught in an infinite loop of bogus
addresses, I don't want them "benchmarking" my web server by pounding on
it. I also added in a further wrinkle to make the URL's it gives you look
a lot more different, so it doesn't appear to be just sending you right
back to the same site and script. Have a look at
http://fdt.net/cgi-bin/wpoison
Note...for real use, it's probably a good idea to not call it wpoison,
lest the collectors clue in and ignore URLs with wpoison in them. I have
a number of hard links to it, so it can be called by other names...now
that I think about it, it might be nice to shuffle those as well.

Deadbolt(tm): This filters out known e-mail spammers, from an automatically
               update-able lists, provided by E-scrub Technologies. What
               happens when a majority of ISPs are using a filter like this and a
               legitimate e-mail address is accidently put in the list?
               That e-mail address would then be denied by a majority of the
               ISPs.

I looked at this several months ago. It seemed slow and klunky and a bit
more complicated than the average user could handle. I like the idea
though.