Whenver I get junkmail, I open it all up, remove anything with my name (or some other identifier) on it, switch the offers around (Discover gets AmEx offers and vice versa), add some ValPak coupons, and send them back via Business Reply Mail. That way, not only do they get to pay for the postage on the return route, but they have to pay some lackey to open it and throw it away.
JOIN ME! ...in my quest to fight back against junkmail.
--Gooser