The same spammers that are buying the lists with bad addresses right
now.
The current lists have a good margin of good addresses I imagine.
There are many people who reply, to be removed or whatever, that
confirm their address as good. As long as there are good hits the
spamming will continue.
I haven't seen a program like the one mentioned before, or the one
John mentioned. These have the potential to decimate a list of a fair
amount of good addresses, making it virtually worthless.
http://www.hostedscripts.com/scripts/antispam.html
This site has a couple of flaws in my opinion. First, it is an
infinite loop and second it is a single site that can be blocked by
the spam bots when they discover what is going on.
A better solution would be a freeware script everyone could download
and run on their site that generates somewhere between 1000 and 10,000
bogus addresses.
There would be no way to block the single site listed, as everyone
could have it running. It would not be an infinite loop, so instead of
crashing or whatever, the bogus addresses would be added to the lists.
If many people chipped in to run it this would bring the value of
lists down to nothing.
The key is to choose non-existent domains, so the spam has no where to
go. Each spam will simply reside on the spammer's server as attempts
are made to find the domain until a bounce is finally generated.
Imagine millions of bounces after buying a list. Imagine the ISP after
this occurs. Would you want this customer if you ran the ISP?
Another consideration is to use real sounding names, just to make it
very difficult to eyeball the list and remove those that look randomly
generated: (e-mail address removed)
I really think this is a very practical approach in fighting spam.
It's the only one I can think of that will work if spambots find these
scripts at every turn.
I can make a c++ program to generate a random, but real looking list,
but I have never done CGI scripts. If anyone is interested I'll write
it and the list can be added as a linked page on your site, or several
pages can be linked.