Whatever I get junk mail, I check to see if it has one of those "business reply mail" prepaid envelopes. I then shove as much of my other junk mail into that e

Whatever I get junk mail, I check to see if it has one of those "business reply mail" prepaid envelopes. I then shove as much of my other junk mail into that envelope as I can, and mail it back to the company on their tab. This is surprisingly effective at reducing junk mail.