How to combat junk snail mail – take prepaid envelopes that come in junk mail, fill a box with bricks or dirty underwear (the heavier the better = $$ from junk mail sender) and tape the label to the box and mail it! When a sender attaches a prepaid envelope, this means that they have already fronted the cost of you sending in your subscription for air conditioner maintenance or useless magazine subscription, so send them a token of wasted resources back by sending them back a useless box of rocks!