I launched a new project last night... SpamMailBag.com.
Email aliases are setup based on the site I'm accessing... For example: firstname.lastname@example.org is in place for this site (I'll be appending it to random posts for the next couple weeks and also possibly using a more targetted per forum system... just waiting for objects to it in Addicts if their are any)... It will only ever be used on this site and I won't mention other addresses on this site.
All email that comes into the aliases is processed and auto-posted to the blog. This allows people a clean look at exactly what they are dealing with and who harvests from where, how "harvestable" a website is... etc.
I currently have addresses in place for Hi5.com (Social Site), ZDNet (News Site), Enterprise IT Planet (One of JupM's sites... This one will be interesting.. I "incorrectly" subscribed to the newsletter and instead of signing up again, just walked away. And of course my blog ComputerDefense.org... I've also added Taz Forums and I'm open to suggestions for the future.
I just ask that you don't post any actual addresses here as I don't want to skew the results.
I'm also looking to co-ordinate blog postings of this project with email addresses specific to each blog and to get it on digg and slashdot with specific addresses for each of them.. So if you're interested fire me an email or a PM.