Several websites offer to help stop your junk mail: you can spend around ten bucks for a do-it-yourself package, or you can pay a monthly fee for provided services. However, if you are willing to put in the time and effort, you can stop your junk mail yourself, for free. There's a great list of instructions at the site for Obvious Implementations Corporation, obviously.com.
Why worry about junk mail? Not only is it a daily hassle, it drains both the economy and the environment:
1. 100 million trees and 28 billion gallons of water are used to produce junk mail each year;
2. 250,000 homes could be heated with one day's supply of junk mail;
3. Americans receive almost 4 million tons of junk mail every year;
4. Approximately $320 million of local taxes are used to dispose of junk mail annually; and
5. Transportation of junk mail costs about $550 million per year.
Interesting read: "A Declaration of Independence from Junk Mail," by Donella H. Meadows, adjunct professor of environmental studies at Dartmouth College.
Sources: University of Oregon; nativeforestnetwork.org; charityguide.org; ecologicalmailcoalition.org.