I'm sure you've seen these, they are the postcards that are pre-addressed by the person, organization, or corporation interested in getting your money.

They all usually look the same, with the big bold letters in the middle which say "Business Reply Mail" (in all caps), with a little rectangle in the top-right corner where you would normally put the stamp that says "No postage necessary if mailed in the United States", underscored by several black horizontal lines (is there a reason for these?). Since the recipient is interested in your monetary response, they are willing to pay the postage, as stated on all of these postcards: "Postage will be paid by addressee".

I hate these things. They always fall out of a magazine when you are trying to preview it in the store, or even after you have purchased it and are reading it at home. These things alone must be leveling a forest the size of Texas in some South American rainforest.

Sometimes I get frustrated enough with all of these accumulating around my apartment, I just gather them up, leave them blank and dispose of them in a nearby mail dropoff.

If someone sends me subversive junk mail including an envelope marked with this on it, I send them back their junk as it was sent to me. Sometimes doing this requires the junk mail to be cut up to fit inside the reply envelope. Either they think their customer base is really stupid and they have to make sure they don't send back all of the literature, or they are used to people like me... :)