I still think the email-address-as-jpeg solution is prohibitively expensive to reverse; effectively impossible for machines, entirely easy for people.
But it does have drawbacks.
It only works with graphical browsers.
This is a very good point. I mentioned ADA compliance yesterday. To be ADA compliant, if you rendered the e-mail address as a graphic, you'd also have to put the text into the ALT tag. Which would enable it for lynx and sight-limited solutions -- and make putting into a graphic kinda meaningless. So you can't use this approach unless you want to ignore the ADA and lock out your blind users from those functions.
I'm not willing to make that tradeoff. While I'm not going to live or die on the ADA compliance issue, I think it's important to keep it in mind because it forces us to focus on more than the "easy" case or the "geek" case and worry about solutions that work across the spectrum of users, from the AOL newbie to Jay. We can't solve problems just for Jay, or just for Newbies, we have to find a solution that works as well as possible for as many of those groups as possible. ADA compliance is a useful strawman that keeps us focussed away from "I want it this way, so that's the right way".
-- Chuq Von Rospach, Architech chuqui@plaidworks.com -- http://www.chuqui.com/
He doesn't have ulcers, but he's a carrier.