Spam Tracking Website

Back in the days when all we had to worry about was snail mail, mailing list sellers would insert artificial addresses to spot misuse of their mailing lists. (Lists were typically sold for one time use; the buyer could follow up with anyone replying to the first mailing, but could not remail anyone else, or sell the list on to other mailers.)

Following that model, how about a web site that specialized in submitting artificial email addresses to different registration sites, then reported back on those that misused the information?

Should be easy enough to automate the tracking of the number of responses to each address, and whether the responses came from the original registration domain, and so on.

(Wouldn't help with the bizarre domain-targeted spam, of course, but it should weed out the sites that are reselling email addresses without permission, and those that have been hacked.)

[If this has been done already, I apologise.]