There's a great app for iPhone and iPod Touch that will help you rid your snail mailbox of unwanted junk mail, and it's as simple as taking a picture! Check out PaperKarma.
it's super simple to use - just launch the app and follow the prompts. I've been using PaperKarma for a week now, and take our house off 13 mailing lists. I've got saved profiles for both members of the my household, as well as "Current Resident", and for the former homeowners who still get junk mail here.