At least people sending junk mail have to pay postage, albeit at a lower rate subsidized by the citizens. The apartment manager thoughtfully provides a trash can next to the mailboxes, and each time I toss a fistful of paper spam I take some pleasure at the thought of what I'm costing the damn paper spammers.

Imagine how bad paper spam would be if junk mailers could send it for free like in the email system. That's why I think that the key to curtailing email spam is to charge for it, instead of the present system whereby email's free and subsidized by general ISP fees. Changing the economics always changes the incentives and disincentives.